Mental Arithmetic
40 free practice questions with explanations
PassNova has 40 free QTS Professional Skills practice questions on Mental Arithmetic, each with a clear explanation. Practise them in the browser with instant feedback — 100% free, no sign-up, on any device. Updated for 2026.
Mental Arithmetic: example questions & answers
40 worked examples with answers and explanations below. Practise them in the browser with instant feedback on every answer.
A class has 28 students. 25% are absent today. How many students are present?
- A7
- B14
- C21✓
- D25
Answer: 25% of 28 = 7 absent. Therefore 28 - 7 = 21 present.
A teacher needs to divide £240 equally among 8 students for art supplies. How much per student?
- A£35
- B£30✓
- C£25
- D£20
Answer: £240 ÷ 8 = £30 per student.
A school buys 6 boxes of textbooks with 15 books per box. How many books in total?
- A80
- B90✓
- C100
- D110
Answer: 6 × 15 = 90 books total.
What is 50% of 144?
- A48
- B72✓
- C96
- D108
Answer: 50% means divide by 2. 144 ÷ 2 = 72.
A test has 80 marks. A student scores 60 marks. What is their percentage score?
- A75%✓
- B65%
- C80%
- D60%
Answer: (60 ÷ 80) × 100 = 75%.
How many minutes are in 3 hours and 45 minutes?
- A180
- B195
- C215
- D225✓
Answer: 3 hours = 180 minutes. 180 + 45 = 225 minutes.
A lesson starts at 2:15 PM and lasts 50 minutes. What time does it end?
- A2:50 PM
- B3:15 PM
- C3:00 PM
- D3:05 PM✓
Answer: 2:15 + 50 minutes = 3:05 PM.
What is 10% of 350?
- A25
- B35✓
- C50
- D70
Answer: 10% of 350 = 350 ÷ 10 = 35.
A school has 200 Year 7 students. 15% take drama as an option. How many?
- A15
- B20
- C25
- D30✓
Answer: 15% of 200 = (15 ÷ 100) × 200 = 30.
Divide 180 by 6.
- A25
- B30✓
- C35
- D40
Answer: 180 ÷ 6 = 30.
A teacher marks 40 papers in 2 hours. How many per hour?
- A15
- B20✓
- C25
- D30
Answer: 40 papers ÷ 2 hours = 20 papers per hour.
What is 33% of 99?
- A25
- B30
- C33✓
- D36
Answer: 33% of 99 ≈ 33 (one-third of 99).
A class score an average of 64 marks out of 100. What percentage is this?
- A68%
- B62%
- C58%
- D64%✓
Answer: 64 out of 100 is 64%.
How many quarters are in 6?
- A12
- B18
- C24✓
- D30
Answer: 6 ÷ 0.25 = 24 quarters.
A school spends £3,600 on resources. If 20% is spent on books, how much?
- A£600
- B£700
- C£800
- D£720✓
Answer: 20% of £3,600 = (20 ÷ 100) × 3,600 = £720.
What is 1/4 of 200?
- A25
- B40
- C50✓
- D75
Answer: 1/4 of 200 = 200 ÷ 4 = 50.
A test is marked out of 120. A student gets 90 marks. What is their percentage?
- A65%
- B75%✓
- C70%
- D80%
Answer: (90 ÷ 120) × 100 = 75%.
Class attendance is 92%. If there are 25 students, how many are present?
- A22
- B23✓
- C24
- D25
Answer: 92% of 25 = 0.92 × 25 = 23 students.
What is 2/5 as a percentage?
- A50%
- B25%
- C20%
- D40%✓
Answer: 2/5 = 0.4 = 40%.
A school trip costs £480 for a group. If split among 12 students, cost per student?
- A£40✓
- B£35
- C£50
- D£45
Answer: £480 ÷ 12 = £40 per student.
What is 15% of 80?
- A8
- B10
- C12✓
- D15
Answer: 15% of 80 = 0.15 × 80 = 12.
A teacher has 3 hours for lessons. If one lesson is 1 hour 30 minutes, how much time remains?
- A75 min
- B45 min
- C90 min✓
- D60 min
Answer: 3 hours = 180 minutes. 180 - 90 = 90 minutes (1 hour 30 minutes).
What is 3/4 of 160?
- A100
- B110
- C120✓
- D130
Answer: 3/4 of 160 = (3 × 160) ÷ 4 = 480 ÷ 4 = 120.
A test has 50 questions. 70% are multiple choice. How many are multiple choice?
- A30
- B35✓
- C40
- D45
Answer: 70% of 50 = 0.7 × 50 = 35 questions.
What fraction is equivalent to 25%?
- A1/2
- B1/4✓
- C1/5
- D1/3
Answer: 25% = 1/4.
If a classroom has 32 desks and 4 are broken, what percentage are working?
- A78%
- B88%✓
- C82%
- D85%
Answer: Working = 32 - 4 = 28. (28 ÷ 32) × 100 = 87.5% ≈ 88%.
What is 20% of 250?
- A40
- B50✓
- C60
- D70
Answer: 20% of 250 = 0.2 × 250 = 50.
A school budget is £100,000. 30% goes to staff. How much is that?
- A£30,000✓
- B£35,000
- C£25,000
- D£40,000
Answer: 30% of £100,000 = 0.3 × 100,000 = £30,000.
If 18 out of 24 students pass, what is the pass rate percentage?
- A70%
- B72%
- C75%✓
- D78%
Answer: (18 ÷ 24) × 100 = 75%.
What time is 2.5 hours after 9:30 AM?
- A11:30 AM
- B1:00 PM
- C12:30 PM✓
- D12:00 PM
Answer: 9:30 AM + 2 hours 30 minutes = 12:00 PM.
What is 5/10 as a percentage?
- A40%
- B60%
- C50%✓
- D70%
Answer: 5/10 = 1/2 = 50%.
A class of 36 students has a 75% attendance rate. How many are absent?
- A9✓
- B12
- C15
- D18
Answer: Present = 75% of 36 = 27. Absent = 36 - 27 = 9.
What is 1/3 of 90?
- A20
- B25
- C30✓
- D35
Answer: 1/3 of 90 = 90 ÷ 3 = 30.
If test scores range from 0-100 and a student scores 85, how far from top?
- A10
- B15✓
- C20
- D25
Answer: Distance from 100 = 100 - 85 = 15.
What is 40% of 150?
- A50
- B55
- C60✓
- D65
Answer: 40% of 150 = 0.4 × 150 = 60.
A PE class has 28 students divided into 4 teams. Students per team?
- A5
- B6
- C7✓
- D8
Answer: 28 ÷ 4 = 7 students per team.
What is 12% of 200?
- A20
- B24✓
- C28
- D32
Answer: 12% of 200 = 0.12 × 200 = 24.
A lesson runs from 1:45 PM to 2:35 PM. How long is it?
- A55 min
- B45 min
- C60 min
- D50 min✓
Answer: 2:35 PM - 1:45 PM = 50 minutes.
If 30 out of 50 tasks are completed, what percentage remain?
- A40%✓
- B30%
- C50%
- D60%
Answer: Completed = 30, Remaining = 20. (20 ÷ 50) × 100 = 40%.
What is 1/5 of 125?
- A20
- B25✓
- C30
- D35
Answer: 1/5 of 125 = 125 ÷ 5 = 25.