Question

Amya spends 2 hours doing her homework. She daydreams about a robot that could do her homework in 10 minutes. If Amya did have that robot, how long would it take them together to complete her homework?

Answer 1

t=34.64 mins

Explanation:

let Arya be A, Robot be B and Combined time be t

`A+B=(1)/(t)\\A=(1)/(t+120)\\B=(1)/(t+10)\\(1)/(t+10)+(1)/(t+120)=t\\(1)/(t+10)=(t+120-t)/(t+120)\\t^2+120t=120t+1200\\t^2=1200\\t=34.6410`