### Video Transcript

Thirds

In this video, we will learn how to
divide shapes into three equal parts, name each part as a third, and say the number
of thirds in a whole.

Here’s a delicious, freshly baked
apple pie. If we need to share the pie between
three people, we will need to cut the pie into three equal pieces. Equal pieces means that each slice
of the pie is the same size. We’ve cut the pie into three equal
slices. When we divide a shape into three
equal parts, we call each part a third. So, each slice of the pie is a
third of the pie. There are three slices or three
thirds in a whole pie. Three thirds make one whole.

This circle has been divided into
thirds, and one-third has been shaded pink. One-third of the circle is
shaded. This semicircle has been divided
into thirds, and one-third has been shaded green. We can divide triangles into
thirds. How much of this triangle is shaded
red? One-third has been shaded. We can also divide squares into
thirds and rectangles. So, we’ve learned that a third is
one out of three equal parts. We’ve also learned that three
thirds make one whole shape. Let’s try some practice questions
now to help us identify thirds.

This circle is divided into three
equal pieces. What is the name for each
piece?

We’re shown a circle which has been
divided into three equal pieces. When we divide a shape into three
equal parts or three equal pieces, we call each piece or each part a third. The circle has been divided into
three equal pieces, and the name for each piece is a third.

This rectangle is divided into
three pieces. Is each piece a third?

In this question, we’re shown a
rectangle, which has been divided into three pieces. We’re being asked if each piece is
a third. This is one of the pieces. Here’s another of the pieces, and
here’s the third piece. What do you notice about the pieces
of this rectangle? They’re all different shapes, and
they’re all different sizes. We can’t call these pieces thirds
because a third is when we divide a shape into three equal parts. A third is one of three equal
parts. The pieces of our rectangle are not
equal. So, the answer to the question “Is
each piece a third?” is no. The rectangle has been divided into
three pieces, but they’re not equal pieces.

Liam has two-thirds of an
orange. Does he have more or less than a
whole orange?

We know that Liam has two-thirds of
an orange. Does he have more or less than a
whole orange? We can imagine that this circle is
a whole orange. The circle has been divided into
thirds or three equal pieces. If we draw Liam’s two-thirds on our
orange, we can see if he has more or less than a whole orange. Here’s one-third, two-thirds. We place Liam’s two-thirds of an
orange onto our whole orange. Now, we can see that one-third of
the orange is missing. Two-thirds of an orange is less
than a whole orange. If Liam has two-thirds of an
orange, then he has less than a whole orange.

Hannah has one-third of a
rectangle. How many more thirds does she need
to make the whole rectangle?

In this question, we’re shown a
rectangle. And we’re told that Hannah has
shaded one-third of it. We’re asked how many more thirds
she needs to make a whole rectangle. We sketched a rectangle and shaded
one-third. If we divide a shape into three
equal parts, we call each part a third. So, Hannah’s rectangle needs three
equal parts. Here’s one, two, three. We’ve divided Hannah’s rectangle
into thirds or three equal parts.

Hannah had a third of a
rectangle. She needed two more thirds to make
a whole rectangle. We know that a third is one of
three equal parts. We need three thirds to make one
whole shape. If Hannah has one-third of a
rectangle, she needs two more thirds to make a whole rectangle.

What have we learned in this
video? We’ve learned that when we divide a
shape into three equal parts, we call each part a third. We’ve also learned that three
thirds make one whole.