laura's rate --- 1/4
lucky's rate ---- 1/2
combined rate = 1/4 + 1/2 = 3/4
time at combined rate = 1/(3/4)
= 4/3 hours
(painting a house in 2 hours ??? , WOW)
laura can paint a house in 4 hours and lucky can paint a house in 2 hours. How long would it take for Laura and Lucky to paint a house together?
1 answer
1 answer