A wall took 6 hours for 4 men to build.

Question

At the same rate,

a) how long would it have taken 10 men?

b) how many men would have been needed to build it in 12 hours? 

Answer 1

The wall takes 4men 6 hours.

 

a. How long will it take 10 men?

 

The way to set up this equation is as follows:

 

4 men take 6 hours. 10 men take X hours.

 

To build the same well,

 

4 * 6 hours = 10 * X hours

 

24 = 10X 

 

X = 2.4hours.

 

It would take 10 men 2.4 hours.

 

b. How many men would need to build it in 12 hours?

 

We set the equations the same way.

 

6 hours for 4 men and 12 hours for X men.

 

6 * 4 = 12 * X

 

24 = 12X

 

24/12 = X

 

X = 2 men.

 

It will take 2 men 12 hours.