Question 107495
lol, let see.,
i doesnt know how to calculate it.,
so this is only my theory.,

suppose sarah done 500 work in 5 hour,
so that means she can make 100 per hour.,
in two hour she can make 200 work done.,
leaving dick 300 work to be done in 2 hour,
so now we know dick can do 150 work in 1 hour..
to finish 500 work, which the same amount of work with sarah.,
500 divide by 150,
and the answer is,

approximately 3 hours 20 minutes.

correct me if i'm wrong,