Question

Jacob can create an app in 24 hours, but if he works together with a friend they can create an app in 16 hours. How long would it take for his friend to create this app alone?

Answer 1

Answer:

Time taken by his friend to create the app alone = 48 hours.

Step-by-step explanation:

Hours needed by Jacob to create an app = 24 hours

$\text{One hour work of Jacob = }\frac{1}{24}$

Let hours needed by his friend in creating the app alone = x hours

$\text{So, one hour work of his friend = }\frac{1}{x}$

The both can create the app in 16 hours.

$\implies \frac{1}{24}+\frac{1}{x}=\frac{1}{16}\\\\\implies\frac{1}{x}=\frac{1}{16}-\frac{1}{24}\\\\\implies\frac{1}{x}=\frac{24-16}{24\times 16}\\\\\implies \frac{1}{x}=\frac{1}{48}\\\\\bf\implies x = 48$

Hence, Time taken by his friend to create the app alone = 48 hours.