Q234
A can write 75 pages in 25 hours. A and B together can write 135 pages in 27 hours. In what time can B write 42 pages ?
A.
17 hrs
B.
19 hrs
C.
21 hrs
AnswerD.
23 hrs
Answer: Option C
Solution
Answer: Option C
Solution:
B's efficiency
= (A + B)'s efficiency - A's efficiency
= 5 - 3
= 2 pages/hour
B's time
2 pages in 1 hour
42 pages in 21 hours