ESE · 2025 Quantitative Aptitude › ArithmeticThree pipes A, B and C can fill a tank in 6 hours. When the tank was empty, all the three pipes were turned on and they worked together for 2 hours, at that instant, pipe C was closed and the pipes A and B continued to work to fill the tank. It took a total of 7 hours from start to fill the tank this way. If pipe C alone is working from the start, the time it takes will be
🔎 The pattern behind this question
This is the same idea UPSC keeps returning to. Start a free trial to see the answer and the full map.
Across examsESE 4 · EPFO 2 · CISF 1
Evolution“Time and Work” tested across 3 years (2015–2025)
Study how UPSC repeats — not just the papers
₹199 / 1 year · Founding Member
Full access unlocks the three things no PYQ PDF gives you:
① Cross-exam learning — see the same idea recur across CSE, CAPF, CDS and NDA.
② Topic evolution — how each idea is framed, year by year.
③ Question intelligence — every PYQ + answer, linked to related concepts and similar questions.
e.g. Round Table Conference: CDS 2017 → CSE 2017 → … → CAPF 2024
15 days free, no card required — then ₹199 for 1 year.
Start your 15-day free trial →