Answer: 6 hours
Step-by-step explanation:
Given, Tim and Jim are working on a school project together.
Tim takes 10 hours to complete the school project.
If Jim worked alone, it would take him 15 hours
Let t be the time they both take if they work together.
Then, [tex]\dfrac{1}{t}=\dfrac{1}{\text{Time taken by Tim}}+\dfrac{1}{\text{Time taken by jim}}[/tex]
[tex]\Rightarrow\ \dfrac{1}{t}=\dfrac{1}{10}+\dfrac{1}{15}\\\\\Rightarrow\ \dfrac{1}{t}=\dfrac{3+2}{30}=\dfrac{5}{30}\\\\\Rightarrow\dfrac{1}{t}=\dfrac{1}{6}\\\\\Rightarrow t=6[/tex]
So, it will take 6 hours to complete the school project together .