Question

a man takes 2 hours to do the dishes and another man takes 4 hours to do the same amount of dishes. how long would it take if they worked together?

Answer 1

1

Answer 2

M1 = 2hr/1wh
M2 = 4hr/1wh

If M1 worked for 1 hour, he would get 1/2 of the dishes done. 30 mins, 1/4. If M2 then took over, it would take him 2 hours to do the rest of the 1/2. 1 hr, 1/4. 30 mins, 1/8. Assuming that they do those tasks SIMULTANEOUSLY:

After 1 hr they would accomplish 3/4
After 1:30 they would accomplish 3/4 + 1/8 + 1/4 = 4/4 + 1/8. The answer is *about* 1:15.