Mathematics
NULL
Medium
Question
A tank is filled in 5 hours by pipes A, B and C. C is twice as fast as B and B is twice as fast as A. How long will A alone take?
A
20 hrs
B
25 hrs
C
35 hrs
✓ Official correct answer
D
Cannot be determined
Community credibility
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A
20 hrs
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B
25 hrs
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C
35 hrs
No member explanations yet for this option.
D
Cannot be determined
No member explanations yet for this option.
Explanation
Rates A : B : C = 1 : 2 : 4. Combined 7 parts = 1/5 ⇒ A = 1/35. A alone takes 35 hours.