Question

If a and b complete a piece of work in 15 days and b alone in 20 days, in how many days a alone can complete the work?

Answer 1

Answer:

60 days

LCM of 15, 20 = 60 (total work)

efficiency ratio (a+b) : b = 4 : 3

if a+b = 4 and

b = 3

then a = 1

so total work ÷ efficiency ratio = no. of days

60÷ 1 = 60 days