Shape of the Space
Logan and Zoe figure out the best shape to set the
chairs up.
Zoe is trying to figure out how to set up the chairs in
the gym. She wants everyone to be able to see, but they
also need to be able to easily get up and get their
awards. Zoe and Logan draw pictures of their ideas. Zoe
thinks about 2 long rows. But the kids toward the ends
won’t be able to see, and the kids in the middle will
have to walk around a lot of people. Logan likes the
idea, but he thinks they should add more rows so that
each row isn’t too long. They decide to make a rectangle
using 4 rows, with 10 chairs in each row.
Zoe chair arrangement idea 2 rows and 2 columns of
chairs. Logans chair arrangement idea 4 rows and
10 columns of chairs.
The Middle Aisle
Zoe wonders how to make it easier for everyone to get
their awards.
Logan suggests that they make a middle aisle for
everyone to walk through.
“Will everyone still be able to see?” Zoe asks.
“Of course! We’ll make sure both sides are symmetrical.”
Logan says. “How?” Zoe wonders.
Logan explains to her that a rectangle has a line of
symmetry right down the middle of it. That means that
both sides of the shape are exactly the same. He draws a
line in the middle of the chairs to show her.
A symmetrical chair arrangement with an aisle
through the center vertically. One side 4 rows and
5 columns. The second side 4 rows and 5 columns.
Another Aisle
Zoe is still worried there might not be enough room
to get around.
Logan has another solution. He says that they can use
symmetry again to help them. He explains that a
rectangle also has a line of symmetry across the middle
of it. Logan draws another line across the middle of the
rectangle.
“Now the top of the rectangle and the bottom of the
rectangle are the same.” Logan explains.
“Oh, I see it now!” exclaims Zoe. “We will have a middle
aisle and one that goes across the rows.”
A symmetrical chair arrangement with an aisle
through the center vertically and horizontally. 4
groups of 2 rows and 5 columns.
The Set Up
Zoe thinks this is perfect!
“I think this is perfect!” Zoe exclaims.
“Everyone can see the stage, and they can get around
easily to accept their awards. Thank you so much,
Logan!”
“You’re welcome!” Logan says.
“I’m always amazed at how many things in the real world
have symmetry. I never thought of a group of chairs as
being symmetrical, but there they are!”
4 groups of chairs, 2 rows 5 columns of chairs.