Question

A and b take 6 hours and 9 hours respectively to complete a work. A works for 1 hour and then b works for two hours. How much work is done im these 3 hours?

Answer 1

A-6 divided by 1 = 1
B-9 divided by 3= 3
1+3=4
hence ¼ part of the work is completed in 3 hrs

if this not correct then check this
A- 1/6hrs to complete work
B- ⅓hrs to complete work
so 1/6 divided by ⅓ = ½
so half of the work is completed in 3 hrs