Question

A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is :

A.

1/4

B.

1/10

C.

7/15

D.

8/15

​

Answer 1

Answer:

8/15

Step-by-step explanation:

say the work is to pack

300 boxes.

so A does 20 boxes daily and B does 15/day

So in 4 days together

they will do

(20*4)+(15*4)

=80+60

=140 boxes out of total 300

or 160 are left

which is 160/300 of total 300

=8/15