Male Narrator: Funding for this program is provided in part by... Female Narrator: We believe in getting outside, playing in the yard, growing things, and connecting with the earth.

We believe good can grow anywhere.

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Male Narrator: And also by Hi, friends.

I'm Caroline, and this is How It's Math, where we discover the surprising ways math shows up in the real world and in amazing careers.

Today, we have a very special episode filled with big numbers, important problems, and people who use math to help others every single day.

First, we're heading out to meet the animal experts at the zoo, where math helps plan meals and care for wildlife.

Next, we go behind the scenes with a radiologic technologist who uses measurement, angles, and precision to capture images that help doctors keep us healthy.

After that, we'll visit a food bank to learn how large numbers help teams organize, sort, and distribute meals to families in their community.

Finally, we're going to explore decimals with an eye doctor who will show us how careful calculations help people see the world more clearly.

From animals to eyes, you're about to see that math isn't just something you do in school, it's something people use to make a difference every single day.

Let's get started.

♪ Doodly doodle, doodly doodle ♪ ♪ doodly doodles and digits ♪ ♪ Area, symmetry, fractions too ♪ ♪ It's all here for you ♪ Have you ever wondered what it takes to feed hundreds of animals at the zoo?

It's not just scooping out food, it's math.

At the Toledo Zoo, zookeepers use math every single day to make sure animals get just the right amount of food to stay happy and healthy.

From measuring buckets of fish for penguins to cutting up fruit for primates, math is the secret ingredient in every meal.

Let's go behind the scenes to see how numbers keep the zoo running.

My name is Carmen Valante and I'm a Commissary Steward at the Toledo Zoo.

It's kind of like working in a grocery store for animals.

We put together various diets and help order diets for all the animals and we prep fruits, vegetables, meat, fish, all different kinds of -- basically any food type that they would need, even enrichment items like cranberries, cherries, strawberries, stuff like that.

Popcorn.

An enrichment item is something that might not necessarily be a part of an animal's everyday diet, but it's kind of like a treat, like a dog or a cat treat.

What does a typical day look like?

So we get here before everybody else does.

Like today, I came in at 5:30 in the morning, and then we load up our truck for all the various buckets and feed bags and anything else that the keepers order for a particular area, and then we deliver it all throughout the zoo.

So we go basically to every building, and we drop off everybody's food, and then usually we come back and we're prepping food for the rest of the day, like cutting the produce and measuring out produce and prepping buckets and all that kind of stuff.

How does a zoo use math?

We use math.

We're obviously measuring things every day, so the animals get a certain amount of food every day that the keepers will cut up.

We're also doing things like calculating an increase in a diet if the vet staff decides that the animals need a little bit more food, especially for like, nursing moms, if there's babies involved.

Usually they get a little bit of a bump, because it's hard being a mom, and there's extra nutrition needed there.

And then, obviously, as the baby grows, they need more and more food.

Also the other direction, as far as a decrease goes, if maybe an animal is gaining a little bit too much weight, and we can do a diet decrease, as far as cutting a little bit of a certain amount of food or a certain type of food out to drop the weight a little bit.

And then also, when we get a new animal.

If we get more of a certain animal in, then we need to increase the entire group's amount of food.

Why is it important to be precise in your position?

Going back to like an animal's weight is -- obviously, if I were to accidentally measure a bunch of extra, especially fruit with some animals, certain species, like we don't want a lot of reptiles to get a lot of sugar and things like that.

So if we were to give them too much for a long period of time, we could actually accidentally harm them.

So that's why we weigh things out, and then the keepers even kind of re-weigh things out so that we know that it's accurate.

We have large animals that are obviously eating like big scoops of grain every day.

But then we have little animals that are only eating even like a tablespoon of a certain ingredient, like some of our birds, for example, that will only get half a cup of papaya or something like that.

So it's really important even for smaller animals, to be really accurate, because it can affect them quicker because they're so small.

What tools do you use when using math?

Carmen Valante: So we use scales a lot, just for easy grams, kilograms, pounds, things like that.

But we do have, like, measuring cups we use, and then we have labeled containers for like quarts and liters and things like that.

So a lot of different containers as far as they have -- they have the measurement written on it.

But we also have to -- we know how much to put in that container.

So we have a lot of different animals that eat peppers.

A lot of our primates eat peppers.

So the gorillas, the orangutans, a lot of our smaller primates like lemurs and Colobus monkeys eat peppers.

And so a week, we usually go through five boxes of green peppers and about one box of red peppers, because there are even some animals that prefer red peppers over green peppers.

So we do have to make sure that we have a little bit of a variety each week for that reason.

The zoo needs to order enough peppers for the week.

Caroline: The animals eat about five boxes of green peppers and one box of red peppers.

There are 40 peppers in each box.

How many peppers does the zoo need to order in all?

[clock ticking] 240 peppers.

First, I started by finding the total amount of boxes, five green pepper boxes plus one red pepper boxes equals six boxes.

Then I multiplied 6 boxes times 40, because that's how many peppers are in each box, which gave me 240 peppers in all.

Did you get it correct?

How did you get to the position you're at today?

My degree is, I'm a Bachelor's in Biological Sciences, so I do have a four year degree, and I always knew that I wanted to work with animals.

Carmen Valante: I really like birds, so I started off in birds, and then I eventually moved into commissary.

I always loved the zoo when I was a kid.

I was in the zoo all the time when I was a kid for field trips and stuff like that.

Do you have any advice for us?

I guess, particular to me personally, I was always -- I always really struggled with division, and not so much on multiplication.

But I do have to use a little bit of division pretty often here, as far as calculating a percentage difference or percent gain or loss, and it's really not that bad.

Once you do it a bunch of times, you get better at it.

My name is Carmen Valante.

I'm a Commissary Steward here at the Toledo Zoo, and this is How It's Math.

Have you ever gotten an X-ray after a fall?

Radiologic technologists are the experts who take those pictures, helping doctors see what's going on inside our bodies.

Did you know that they use math to do it?

One of the most important tools they use is something you might already be learning, angles.

Today, we'll discover how radiologic technologists use angles to make sure the X-rays are just right and help people feel better faster.

My name is Samantha, and I am a Radiologic Technologist.

Caroline: Radiologic technologists are the people who take X-rays to help diagnose patients.

What is an X-ray?

An X-ray is simply just a picture of either your hand, your arm, it could be any of the 206 bones in our body.

Samantha Shumaker: An X-ray is able to help diagnose patients, whether it be broken bones or any other internal issues that might be going on to detect cancer, pneumonia, anything like that.

How do you use math?

Samantha Shumaker: Math is used every day.

With every single patient, actually, that walks through our door, we're incorporating math.

Most of the part is using angles.

Angles help us to position the patient correctly.

We also have to use our equipment to operate and utilize angles.

That way, we have perpendicular angles, where my tube is perpendicular to the board behind me.

It's usually how we start out an image.

Then we can utilize the patient, we use 45 degree angles.

We do have a measuring scale, a degree here on our tube that helps us be exact if we are looking at like 15 degrees or 35 degrees.

Those kind of degrees we can't quite see eyeballing it.

Why is it important to be precise in your position?

It's very important to be precise.

We are using these images to help diagnose patients in whatever ailments may be going on.

So to be exact at 45, to be exact at 90 degrees, being able to turn the patient and turn your angles helps to open up certain joint spaces in whichever area that you're looking at in the body.

[bell ringing] What does a typical day look like?

So most of our patients are walk in.

So they are not scheduled, so they can come in anytime through the day as long as we're -- building is open and operating.

Certain exams may only require two pictures.

Certain exams may require five pictures.

And then when you get multiple patients that have five pictures, it adds up.

We see about over 300 images a day.

Caroline: In the first half of the day, there were 24 patients who came in to get X-rays.

Each person got three X-rays taken.

How many X-rays were taken in total?

[clock ticking] Seventy two X-rays.

Here's how I did it.

There were 24 patients, and they each got 3 X-rays each.

So I did 24 times 3.

24 times 3 is 72.

Did you get it correct?

Did you enjoy math growing up?

I did not.

So I know that in more so middle school, I did not enjoy math.

It wasn't until though, that I had the ability to talk with my math teacher a whole lot more.

And I'm very thankful for that math teacher, because he was able to spend that extra time to help me understand math, so that I would learn to enjoy it.

What's your favorite thing about math?

Regarding the physics and stuff behind the X-ray, being able to take it.

And as to why, we do have equations where you get to solve for X. So, as long as three of the four factors are given, it's quite easy to kind of figure out what you need to do to change your technique or change your distance, and how to compensate for that.

How did you get to the position you're at today?

My degree, I came out of school with an associate's degree.

So, it's nothing that needed to be a bachelor's or your master's, anything higher.

Now you can seek out a higher degree, but it's not necessary for this field.

So, two years plus a year of maybe general education.

So, and I still love what I do.

So there you have it.

If angles excite you, maybe a career as a radiologic technologist is right for you.

My name is Samantha, and I am a Radiologic Technologist, and this is How It's Math.

There are many different ways that you can support different families in your community.

One way that people support their community is through a food pantry.

Today, we get to go behind the scenes to see how a food pantry uses math every single day.

Kathy Hoff: Hi, I'm Kathy Hoff.

I'm the Executive Director at People In Need, Inc.

of Delaware County, Ohio.

I am in the food pantry.

This is where our volunteers will shop for families that come to our pantry services.

How do you use math?

We use math every day from counting items Kathy Hoff: to make sure we're giving people the appropriate amount for a three or four day meal supply.

We serve about 400 residents a week.

We need to prepare to have enough food to meet that need of 400 families.

That involves a lot of math as well, because some families have one to two people in their family, some families have 10 people.

We need to make sure that we're ready to serve any size family in our pantry when they come here.

If we see that this crate will hold seven boxes and then eight, nine, ten, we know that this is ten, so we're going to need 40 more of those, because 40 times 10 is 400.

A lot of our food comes from Mid-Ohio Food Collective, which is in downtown Columbus.

So they actually come to People In Need with fresh produce or our canned food items.

We get about half of what we distribute through drives that are done in the community.

From one school food drive, we usually will have enough to serve 200 families.

Two hundred families is what most schools will do a drive for.

Do you use decimals?

When people make donations, we weigh it on a scale in our warehouse, and then we assign it $1 value.

Kathy Hoff: Food by pounds is $1.70.

So, every pound of food that we have that comes in donated to us, we have to multiply that by $1.70 to give the value of what that contributed good was.

How do you have to estimate?

A part of our budgeting process is to estimate for the next year, how many people we think we're going to serve, and then assign $1 value to how much in contributed goods we need to raise, Kathy Hoff: and then how much in dollar amounts we need to raise.

So we have to give a guesstimate on what it would cost to feed those people.

What is something that might surprise students about your job?

People who come to a food pantry can be anyone.

We have other people that may have experienced a job loss or something else that really requires them to come to our food pantry.

And the really cool part about that is a lot of those people who utilize our services, when things get better for them, they are now a donor.

They will come back and give back to their community.

The food pantry needs 500 boxes of cereal for the week.

They currently have 345 boxes.

How many more boxes of cereal do they need?

[clock ticking] I did 500 minus 345 equals 155 cereal boxes.

Kids can help by giving to other families or kids what you like to eat.

Kathy Hoff: If it's something that you would eat, I guarantee you there's another kid who would eat that too.

You give what you love to make somebody else be so happy.

This is People In Need, and this is How It's Math.

Did you know that when you get glasses, you actually have to use math.

Join us today as we go behind the scenes of an optometrist, where we discover how she uses fractions, decimals and all sorts of math.

Let's get into it.

I am Ann Morrison, and I am an Optometrist and Assistant Professor at The Ohio State University College of Optometry here in Columbus, Ohio.

An optometrist is an eye doctor.

An eye doctor or an optometrist helps you see.

People say optometrists are who prescribes glasses and contacts, which help you see the world better.

But optometrists do a little bit more than that.

They can help manage and diagnose problems with the eyes and visual systems.

Sometimes the eyes don't like to work together or focus as well as they should, which can affect kids in the classroom.

We can do things to help manage and treat those conditions to help them succeed visually.

How do optometrists use math?

We as eye doctors use math every single day.

I think the most obvious way that we use math is the prescription that we -- that are put in glasses and contacts.

So, when we have a prescription, those are all numbers, and there's three different components generally to a prescription for glasses or contacts, we have to use those numbers to calculate them.

Ann Morrison: So, there's three components to a prescription.

There's the sphere component, the cylinder component and an axis component.

And there's three different numbers that are written together, and they can be a plus or a minus.

So, a plus lens is what we prescribe for our farsighted patients.

A minus lens is what we prescribe for our nearsighted patients.

The sphere part and the cylinder part are written in plus or minus, and that tells us what power that they need, whether they're nearsighted or farsighted.

How do you get your prescription?

When you come in to the eye doctor, we look and use this instrument called the phoropter, which comes in front of your eyes, and that's where you see doctors spinning dials and spinning lenses in front of you.

Each one of those lenses has a different number assigned to it.

Those numbers we read off, and then we write it down and prescribe it.

And that's what gets put into the glasses or contacts themselves.

Those prescriptions are simply how powerful those lenses are to help you see.

What math unit do you use when you write down a prescription?

The units that we use to write these prescriptions are called a diopter.

A diopter is the inverse of the focal power of the lens.

Ann Morrison: One diopter is one over the focal length in centimeters and then we convert it.

So we use it -- we have our own special language in optometry that no one else really uses, and that's what we use to write your prescription.

We also use another unique unit in optometry called a prism diopter.

So, talked about diopters, another one that we use is called a prism diopter, which is often how we assess where the eyes like to be in space.

So prism diopter, it is a prism that we use to measure and we hold it up to a patient's eyes and do various things with it to help move the images in the world.

So a prism shifts images, and we use that a lot to characterize different parts of the visual system.

Sometimes patients have what's called an exophoria, which is where their eyes rest outwards, and sometimes they have an esophoria, where their eyes rest inward.

We use math when we are calculating contact lens prescriptions actually.

I have to use math intuitively called vertexing.

So your glasses sit off of your eyeballs, right?

So, your glasses sit on your nose, and so there's a distance between the glasses and your eyes, whereas a contact lens sits directly on the eye itself, and because of that, that change in the distance, it can actually change the power that you need to see clearly.

So, I have to use math when I am considering -- the prescribing a contact lens prescription based off of a glasses prescription.

How do you use decimals?

So, I do use decimals all the time.

In our world, we work in what's called quarter diopters.

I have to be really good at fractions and adding fractions and subtracting fractions.

Even though we work with fractions, we actually write them in decimal form.

So, I go back and forth all the time with fractions and decimals.

So, when I say a quarter diopter, a lot of people might think 1 over 4, but actually, in my mind, I'm thinking 0.25 is how I typically think of it.

And so when I do my steps and what we read off our instruments are actually in decimal form.

So when we say half a diopter, it's 0.5.

When we say three quarters of a diopter, it's 0.75.

So, I actually utilize decimals quite frequently as well, and I have to be able to go back and forth between thinking of it in fraction form and thinking of it in decimal form.

Why is it important to be precise in optometry?

Being precise as an optometrist is very important, because if things aren't exactly right, that could affect our patients.

Everyone is sensitive to how they see the world, and so if those numbers aren't exactly correct, that could affect how well a patient does with their new pair of glasses or contacts.

What else do you do to help patients?

As an eye doctor, I can also prescribe medications.

When we prescribe medications for different eye diseases, like maybe an eye infection or maybe an eye is really irritated, then we need to prescribe a steroid.

I often work with children, and so when we do that, we have to make sure that we adjust for the fact that children don't have adult bodies, right?

Adults, we typically prescribe similarly, right?

And you're done growing, so you just prescribe the same thing.

But for a child, as they're growing and developing, their bodies are not the same size.

They don't metabolize things the same way.

And so I have to do calculations based on a child's weight.

But when a kid comes in and let's say, they have an eye infection, I need to prescribe them an antibiotic.

I've got to get their weight and make sure that we are prescribing their medication based on how big or little they are.

Quick questions with an optometrist.

Why is it important to show your thinking?

It's really important in my career to show my thinking, because I think it helps our patients understand what can help them.

When I think about what makes a really good eye doctor and someone that people like Ann Morrison: to come back to and see from year to year, is telling them your thought process and telling them how you came to the conclusion you did, right?

And if you think about your own experiences when you go to the doctor, you probably feel more comfortable with someone who's talking you through how things are going.

That's one aspect where I think educating your patients and telling them about how you came up to your conclusions is going to be really helpful and make them feel more comfortable.

What is your best advice for current math students?

I think my advice would be -- when I think back to my elementary school days and learning math, I found myself getting frustrated Ann Morrison: when things didn't come to me right away.

I remember taking things home and getting upset because something wasn't clear to me right away.

And I think my advice is just to be persistent.

It's not something that always comes naturally and it doesn't have to.

Practice is what you have to do to get better at it.

I still have to practice things every day to get better at it.

It's a skill, right?

So, it's not something that it comes naturally to everybody.

No, it's cliche, but practice really does make perfect in a sense, right?

And it doesn't have to be your favorite thing in the world but it's something you use enough that I think it's worth pushing through.

Last year, your eye prescription was 2.25, this year, your prescription was 2.75.

What is the difference in your prescription from last year to this year?

Make sure you take your time and show your thinking.

[clock ticking] The difference in your eye prescription is 0.50.

Did you get it correct?

A good time to go see the optometrist would be if you're struggling to see things clearly, things are blurry and not as clear at all ranges.

So, it can be at distance, it could be up close.

At the end of the day, I love that math is really -- numbers are really optometry, and I think that's really cool.

And sure, we manage diseases and prescribe medications, that's great.

But at the end of the day, I went into this to help people see, and the way people see are by doing the math right in front of me.

So, I spin the dials on the phoropter, I come up with a number, and then I can help someone see better, simply by using numbers every day.

I am an optometrist, and that's How It's Math.

Wow.

Look at all the ways math helps people care for animals, support their communities and improve our health.

Today, we saw professionals using numbers to plan diets, capture medical images, manage resources and protect our eyesight.

Whether it was measuring, estimating, multiplying or analyzing data, math was the center of every decision.

The next time you solve a problem in class, remember you're practicing the same skills that real experts use every day in incredible careers.

Thanks for exploring with us on How It's Math.

I'm Caroline, and I can't wait to discover more real world math with you next time.

Bye.

Male Narrator: Funding for this program is provided in part by, Female Narrator: We believe in getting outside, playing in the yard, growing things and connecting with the earth.

We believe good can grow anywhere.

That's why we're committed to GroMoreGood, everywhere.

And also by...