Area of rectangle 12 m by 3 m

Step by step

The question

Question: find the area of a rectangle 12 m long and 3 m wide.

1 What area means

Area is how much space is inside.

We count the 1 by 1 squares that fit.

One row has 12 squares.

There are 3 rows.

2 Length times width

So the area is length times width: A = length × width.

Squares in a row, times the rows.

Now put the numbers in: length = 12 and width = 3.

12 times 3 is 36.

We count squares, so the unit is m².

So the area is 36 m².

3 Check

Let's check: count row by row.

3 rows of 12 squares.

We get 36 again.

So the area is right!

Let's look back.

First: what area means.

Then: length times width.

Last: check.