Question

John can create an app in 6 weeks while Ben can do the same job in 12 weeks. How many weeks would it take them to create an app together? Please explain

Answer 1

`4\ weeks`

Explanation:

we know that

John can create an app in 6 weeks

so

In 1 week can create 1/6 of app

and

Ben can create an app in 12 weeks

so

In 1 week can create 1/12 of app

Together in 1 week can create -----> 1/6+1/12=3/12=1/4 of app

so by proportion

`(1)/((1/4))(week)/(app) =(x)/(1)(week)/(app) \\ \\x=1/(1/4)\\ \\x=4\ weeks`