Andrew can paint the neighbor's house 3 times as fast as Bailey. The year Andrew and Bailey worked together, it took them 2 days. How long would it take each to paint the house?

Andrew can paint the neighbors house 3 times as fast as Bailey.

The year Andrew and Bailey worked together, it took them 7 days.

How long would it take each to paint the house?

:

Let t = time required by A to do it alone

then

3t = time required by B to do it alone

:

Let the completed job = 1

:

7%2Ft + 7%2F%283t%29 = 1

Multiply equation by 3t to get rid of the denominators, results:

21 + 7 = 3t

28 = 3t

t = 28%2F3

t = 91%2F3 days, Andrew alone

then

3*91%2F3 = 28 days, Bailey alone

:

:

Check solution on calc using decimals

(7/9.33) + (7/28) = 1.00

only 10/60 isn't equivalent

hope this : )

a. is correct