PrepRung
Sign inSign up free

CAT 2017 Slot 1 · Quant · Pipes and Cisterns · easy

Pipe A alone fills a tank in 12 minutes, pipe B alone fills it in 15 minutes, and pipe C alone empties a full tank in 10 minutes. Starting with an…

Single correct option

Pipe A alone fills a tank in 12 minutes, pipe B alone fills it in 15 minutes, and pipe C alone empties a full tank in 10 minutes. Starting with an empty tank, all three pipes are opened together. In how many minutes will the tank be full?
  1. A. 15
  2. B. 18
  3. C. 20
  4. D. 24
Show answer and solution

Answer: (C) 20

Take tank capacity = 60 units (LCM of 12, 15, 10).

A fills 5 units/min, B fills 4 units/min, C empties 6 units/min.

Net = 5 + 4 − 6 = 3 units/min, so the tank fills in 60/3 = 20 minutes.
Report a mistake

Original question written in the CAT 2017 Slot 1 pattern and checked twice for the correct answer. Not an official question paper. How we write and check questions · Corrections policy · Report a mistake