# pipes P and Q would fill a cistern 18 and 24 minutes respectively. Both pipes being opened, find when the first pipe must be turned off so that the cistern may be just filled in 12 minutes? with Answer - Maths Mcqs | TestPrep

> Solved MCQ: pipes P and Q would fill a cistern 18 and 24 minutes respectively. Both pipes being opened, find when the first pipe must be turned off so that the cistern may be just filled in 12 minutes? Correct Answer: B. after 9 mins. Verified answer explanation for FPSC, PPSC, MDCAT, NTS, and CSS competitive exam preparation.

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# pipes P and Q would fill a cistern 18 and 24 minutes respectively. Both pipes being opened, find when the first pipe must be turned off so that the cistern may be just filled in 12 minutes?

Direct Answer & Quick Reference

The correct option is **B. after 9 mins**.

A. after 12 mins

B. after 9 mins **(Correct Answer)**

C. after 8 1/2 mins

D. after 10 mins

✨ Explain with AI

Verified Key: B. after 9 mins
Solved by 3,859+ students

Verified against official examination board answer keys and standard curriculum textbooks.

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*Source: https://test-prep.blog/mcq/pipes-p-and-q-would-fill-a-cistern-18-and-24-minutes-respectively-both-pipes-bei-bd076976-45c9-4ee5-a534-d50445af61e6*
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