Question

Rahm spent 2 1/2 hours writing an essay. It took him 4 times as long to finish his science project. How long did it take rahm to write the essay and finish the science project.

Answer 1

Let's do the math, 2.5+2.5+2.5+2.5( 4times) is 10hrs+2.5= 12.5hrs

Answer 2

Answer:

Time taken by Rahm to write the essay and finish the science project = 12.5 hours    

Step-by-step explanation:

$\text{Time spent by Rahm on writing the essay = }2\tfrac{1}{2}=\frac{5}{2}\:\:hours\\\\\text{Now, Rahm took 4 times as long to finish the science project}\\\\\implies\text{Time took by Rahm to finish the science project = }4\times \frac{5}{2}=10\:\:hours$

Now, we need to find the total time spent by Rahm to finish the both writing the essay and the science project.

$\text{Therefore, Total time taken by Rahm = }\frac{5}{2}+10=\frac{25}{2}\:\:hours$

Hence, Time taken by Rahm to write the essay and finish the science project = 12.5 hours