It takes Jake 9 hours longer than Joe to rebuild an engine. Working together, they can do the job in 20 hours. How long would it take each, working alone, to rebuild an engine?

Question

amistre64 · Answer

Jake = j+9

j + j+9 = 20

amistre64 · Answer

2j = 11

j = 11/2 = 5.5 hours .... this doesnt look likeits gonna work out lke i thought lol

anonymous · Answer

let jack do in a hr. and joe in a+9 hr.
in one hr both they do 1/a+1/(a+9). so 20(1/a +1/(a+9))=1 will give you a.

amistre64 · Answer

ahhh.... i didnt do reciprocals lol

anonymous · Answer

darn cuz i had the same answer as amistre....so what the answer if that doesnt work out?