math length of rectangle

Question

a rectangle has an area of 12 m² and a width of 400 cm . what is the length of the rectangle ?

Answer 1

A = 12 m²

 

W = 400 cm = 4m

 

A = LW ⇒ L = A/W = (12 m²) / (4m) = 3m

 

The length is 3m.

 

 

Answer 2

This problem involves two different types of measurements: meters and centimeters.

We want all the measurements in a problem to be same.

 

So let's first convert 400 cm to meters.

 

We know 100 cm = 1 meter (this should be memorized) so 400 cm must be 4 meters 

 

 

This is an algebra problem so in any algebra problem you always want to write out the algebraic equation.

The algebraic equation for area of a rectangle is length times width or
A = L x W.

The problem gives us the area: A= 12 meters squared
And the width: W= 4 meters

 

Let's rearrange the equation to find and isolate length: L = A / W  

Now we just plug in: L = 12 meters / 4 meters

12 divided by 4 = ?