Combined Filling and Emptying – Verified PYQ Authority Guide
Combined Filling and Emptyingis treated here as a focused concept hub. The aim is to show exactly how this concept appears across verified PYQs, which formulas or relationships recur in the solved corpus, and which nearby concepts deserve revision next. Every factual learning cue below is drawn from the existing verified, published and approved English PYQ corpus or from its Knowledge Graph relationships; the hub does not invent unsupported technical claims.
PYQ evidence snapshot
30 verified PYQsare currently mapped to this Concept hub. The represented years include2025. Exam coverage currently includesRRB NTPC Under Graduate Level. Subject context includesQuantitative Aptitude. These values come from live mappings and can expand automatically when new verified PYQs are added.
Most useful verified PYQs to solve first
Start with the actual questions rather than memorising a generic note. The links below are ranked from the mapped corpus using repeat history and editorial quality, while the complete explanation stays on the individual question page.
- A tank is full. Pipes A and B can drain the tank in 10 hours and 15 hours, respectively, while pipe C can fill the tank in 12 hours. Pipes A and…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 10 hours. - Pipe A can fill a cistern in 10 hours, pipe B in 15 hours, and pipe C can empty it in 30 hours. All three pipes are opened together. After 6 hours,…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 12 hours. - Pipes, A and B, can fill a tank in 10 hours. Pipes, B and C, can fill the same tank in 20 hours. If pipe B alone can fill the same tank…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 12 hours. - Pipes C and D can fill a tank of 3,000 litres in 6 hours and 4 hours, respectively. Working together, how many hours will they take to fill a 6,000-litre tank?
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 4.8 hours. - Pipes A, B and C can together fill a tank in 6 hours. After working together for 2 hours, C is closed and A and B together fill the remaining part in…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 14. - Two pipes, A and B, can fill a tank in 20 minutes and 30 minutes, respectively. A waste pipe C can empty it in 60 minutes. All three are opened together. After…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 14 minutes. - A cylindrical pipe has an external radius of 8 cm and an internal radius of 7 cm. If its length is 20 cm, what is the volume of material used in the…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 942 cubic cm. - Pipe X can fill a reservoir in 15 hours and pipe Y can empty it in 20 hours. If both pipes are opened simultaneously and pipe Y is closed after 10 hours,…
RRB NTPC Under Graduate Level · 2025
Use the standard Combined Filling and Emptying method and simplify; the result matches 22.5 hours.
Formula & key-relationship bank from verified solutions
Work/Filling rate = 1 ÷ time; net rate = filling rates − emptying rates
Use these as revision triggers and open the linked PYQ before applying a formula numerically; variable definitions and assumptions belong to the exact solved question.
Core ideas repeatedly reinforced by the solved corpus
- Use the standard Combined Filling and Emptying method and simplify; the result matches 10 hours.
- Use the standard Combined Filling and Emptying method and simplify; the result matches 12 hours.
- Use the standard Combined Filling and Emptying method and simplify; the result matches 4.8 hours.
- Use the standard Combined Filling and Emptying method and simplify; the result matches 14.
- Use the standard Combined Filling and Emptying method and simplify; the result matches 14 minutes.
Exam tips already validated in SRO solutions
- Identify the Combined Filling and Emptying relationship before calculation and keep units/bases consistent.
Common mistakes to avoid
- Using a shortcut without checking its conditions or using the wrong base/unit.
Topic and concept coverage
Mapped topic labels includeTime and Work. The concept trail includesCombined Filling and Emptying. Use these labels as a revision map: move from the broad area to the narrow concept, solve a verified PYQ, inspect the detailed reasoning, and then attempt another question from the same cluster.
Knowledge Graph navigation
Continue withPipes and Cisterns,Time and Work,Arithmetic,Quantitative Aptitude. These are canonical SRO entity links based on the Knowledge Graph and shared question mappings, not keyword-stuffed tag pages.
How to revise this authority page efficiently
- Solve before reading:answer a mapped PYQ first.
- Read the exact explanation:verify the correct principle, formula, distractor logic and common mistake on that question page.
- Move one level in the graph:use the closest concept/sub-topic/topic link rather than opening unrelated content.
- Reattempt:solve another verified PYQ from this hub and check whether the same error repeats.
Quality scope:આ પૃષ્ઠ SRO ના વેરિફાઈડ મેપ કોર્પસમાંથી આપમેળે જાળવવામાં આવે છે. તે કીવર્ડ વેરિઅન્ટ્સ માટે બહુવિધ નજીકના-ડુપ્લિકેટ પૃષ્ઠો બનાવવાને બદલે એક કેનોનિકલ ઓથોરિટી URL ને સમૃદ્ધ બનાવે છે. મેન્યુઅલ ઓથોરિટી લેખો ઓટોમેટેડ એન્જિન દ્વારા ક્યારેય ઓવરરાઈટ થતા નથી.