Problema Solution

Jessie can paint 1.5 times as fast as Fred. How long would it take for each to paint the house alone if it takes 12 hours working together

Answer provided by our tutors

If Jessie takes x hours, Fred Takes 1.5x hoours

1/x+1/1.5x = 1/12

or 2.5/1.5x = 1/12

or, 3 = 1.5x

so x = 2 hours, painting together


If Jessie had been alone she would have had to paint for

2/3 * 2hours =  4/3 of an hour

If Fred had been painting alone he would have had to paint for

3/2 * 2 hours = 6/2 = 3 hours


Jessie would have taken 3 1/3 hours

Fred would have taken 5 hours