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Percentage questions with answers

These percentage questions are the arithmetic that everything else in the paper is built on — profit, interest and data interpretation are all percentage questions wearing a different hat. Each walkthrough uses the fraction equivalent where one exists, because a candidate who reaches for 1/8 instead of dividing by 12.5 finishes the section.

Download the PDF — 15 questions with answers

Free, ungated, no email. This is the percentage questions with answers PDF — the same 15 questions as below, with every worked solution at the back, ready to print.

How to use this set

The 15 questions below are ordered the way an exam block is rather than easiest-first: two gentle openers, then a run of medium, and a hard one every sixth question — 2 of the 15 sit in the hard band. Every question is a percentages.

Work each question on paper before you open its solution. The walkthrough is the method itself, step for step, so reading it first turns a practice set into a reading exercise and teaches nothing. If you are stuck on the method rather than on one question, the method guide is a better place to start than the next question: Percentages: the fraction table that pays.

15 percentage questions with answers

Every question below was generated by the same engine that mints the ComputePrep daily timed drill, and machine-checked before it reached this page — a multiple-choice question validates its own answer against its own options at generation, and ships only with a walkthrough attached. The walkthrough is the engine's own.

Question 1

Percentage drill — no paper.

20% of 150 = ?

  1. 3
  2. 20
  3. 300
  4. 40
  5. 30
Show the worked solution
  1. 20% is 1/5 — so take 1/5 of 150: 30.

Question 2

Percentage drill — no paper.

20% of 85 = ?

  1. 170
  2. 18
  3. 27
  4. 17
  5. 2
Show the worked solution
  1. 20% is 1/5 — so take 1/5 of 85: 17.

Question 3

Percentage drill — no paper.

A value rose from 65 to 104. By what percent did it change?

  1. 120
  2. 60
  3. 50
  4. 70
  5. 38
Show the worked solution
  1. The change is 104 − 65 = 39.
  2. Percentage change is always measured on the ORIGINAL value: 39 / 65 × 100 = 60%.

Question 4

Percentage drill — no paper.

15% of 380 = ?

  1. 6
  2. 57
  3. 58
  4. 67
  5. 570
Show the worked solution
  1. 15% is 3/20 — so take 3/20 of 380: 57.

Question 5

Percentage drill — no paper.

16 is 20% of what number?

  1. 320
  2. 100
  3. 80
  4. 88
  5. 89
Show the worked solution
  1. 20% of the number is 16, so 1% is 16 ÷ 20 = 0.8.
  2. 100% = 0.8 × 100 = 80.

Question 6

Percentage drill — no paper.

400 increased by 20%, then decreased by 25%. Final value?

  1. 380
  2. 400
  3. 350
  4. 360
  5. 480
Show the worked solution
  1. +20%: 400 → 400 × 120/100 = 480.
  2. Successive changes multiply — they never simply add (20−25 ≠ the net change).
  3. −25%: 480 → 480 × 75/100 = 360. Final value: 360.

Question 7

Percentage drill — no paper.

50% of 30 = ?

  1. 25
  2. 15
  3. 16
  4. 150
  5. 20
Show the worked solution
  1. 50% is 1/2 — so take 1/2 of 30: 15.

Question 8

Percentage drill — no paper.

20% of 125 = ?

  1. 25
  2. 35
  3. 250
  4. 3
  5. 15
Show the worked solution
  1. 20% is 1/5 — so take 1/5 of 125: 25.

Question 9

Percentage drill — no paper.

17 is 5% of what number?

  1. 345
  2. 340
  3. 351
  4. 350
  5. 349
Show the worked solution
  1. 5% of the number is 17, so 1% is 17 ÷ 5 = 3.4.
  2. 100% = 3.4 × 100 = 340.

Question 10

Percentage drill — no paper.

17 is 5% of what number?

  1. 345
  2. 85
  3. 310
  4. 22
  5. 340
Show the worked solution
  1. 5% of the number is 17, so 1% is 17 ÷ 5 = 3.4.
  2. 100% = 3.4 × 100 = 340.

Question 11

Percentage drill — no paper.

6 is 20% of what number?

  1. 30
  2. 37
  3. 120
  4. 50
  5. 42
Show the worked solution
  1. 20% of the number is 6, so 1% is 6 ÷ 20 = 0.3.
  2. 100% = 0.3 × 100 = 30.

Question 12

Percentage drill — no paper.

300 increased by 20%, then decreased by 50%. Final value?

  1. 300
  2. 180
  3. 210
  4. 360
  5. 190
Show the worked solution
  1. +20%: 300 → 300 × 120/100 = 360.
  2. Successive changes multiply — they never simply add (20−50 ≠ the net change).
  3. −50%: 360 → 360 × 50/100 = 180. Final value: 180.

Question 13

Percentage drill — no paper.

50% of 40 = ?

  1. 200
  2. 10
  3. 2
  4. 20
  5. 30
Show the worked solution
  1. 50% is 1/2 — so take 1/2 of 40: 20.

Question 14

Percentage drill — no paper.

25% of 84 = ?

  1. 22
  2. 34
  3. 21
  4. 210
  5. 31
Show the worked solution
  1. 25% is 1/4 — so take 1/4 of 84: 21.

Question 15

Percentage drill — no paper.

A value fell from 20 to 12. By what percent did it change?

  1. 80
  2. 50
  3. 60
  4. 40
  5. 67
Show the worked solution
  1. The change is 20 − 12 = 8.
  2. Percentage change is always measured on the ORIGINAL value: 8 / 20 × 100 = 40%.
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Where these questions come from

Most free practice for this topic is a scanned upload or a blog quiz, and neither can tell you a question has exactly one answer. That is the one thing this set can promise: it is minted, not typed. The engine behind it serves ComputePrep's daily timed drill, so the questions here are the same shape as the ones a live round would give you — and there is an unlimited supply of them, which is why this page can be regenerated rather than padded.

If you want the method rather than more questions, Percentages: the fraction table that pays covers the approach, the traps and a worked table. This page and that one deliberately answer different questions: that one is how do I solve these, this one is give me percentage questions with the answers.

FAQ

Which percentage-to-fraction conversions are worth memorising?

Everything down to 1/16: 50, 33.33, 25, 20, 16.66, 14.28, 12.5, 11.11, 10, 9.09, 8.33 and 6.25 per cent. Those twelve cover the overwhelming majority of exam percentages, and each one turns a division into a multiplication you can do in your head.

Why is a 20% rise followed by a 20% fall not a return to the start?

Because the two percentages sit on different bases. The rise is on the original, the fall is on the raised figure. The net effect of successive changes of a and b per cent is always a + b + ab/100, which for +20 and −20 gives −4 per cent.

How do I convert a percentage change into a ratio quickly?

A 25 per cent increase is a multiplier of 5/4; a 25 per cent decrease is 3/4. Working in ratios rather than percentages lets you cancel across a chain of changes, which is how a three-step problem collapses into one fraction.

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