Mathematics
NULL
Medium
Question
P and Q need 8 days for a work; Q and R need 12 days; P, Q and R together need 6 days. How long would P and R take together?
A
7
B
8
✓ Official correct answer
C
9
D
10
Community credibility
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A
7
No member explanations yet for this option.
B
8
No member explanations yet for this option.
C
9
No member explanations yet for this option.
D
10
No member explanations yet for this option.
Explanation
P+R = 2(P+Q+R) − (P+Q) − (Q+R) = 1/3 − 1/8 − 1/12 = 1/8 ⇒ 8 days.