48.
P, Q and R are three typists who working simultaneously can type 216 pages in 4 hours. In one hour, R can type as many pages more than Q as Q can type more than P. During the period of 5 hours, R can type as many pages as P can during 7 hours. How many pages does each of them type per hour ?
A:
14,17,20
B:
15,17,22
C:
15,18,21
D:
16,18,22
The answer is:
C
