Mathematics
NULL
Medium
Question
Pipe A fills in 16 minutes and B empties in 24 minutes. Both open; after how many minutes should B be closed so the tank fills in 30 minutes?
A
20
B
24
C
23
D
None of these
✓ Official correct answer
Community credibility
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A
20
No member explanations yet for this option.
B
24
No member explanations yet for this option.
C
23
No member explanations yet for this option.
D
None of these
No member explanations yet for this option.
Explanation
30/16 − x/24 = 1 ⇒ x = 21 minutes, which is not listed in A–C. So None of these.