Search quizzes/
ReasoningMedium10 questions + 90 practice 60s per questionSSC CGLSSC CHSLRRB NTPC

Mathematical Operations Quiz: Reasoning Practice

10 timed questions on symbol substitution, BODMAS, sign interchange, choosing signs and hidden-rule operations like a # b. Each solved step by step.

Casio calculator JS-20WK
Photo: Mc681, CC BY-SA 4.0, via Wikimedia Commons
Read the notes first (7 min)

Mathematical Operations Quiz: Reasoning Practice

  • 10 questions
  • Medium
  • 60s each

Tip: use keys 1-4 to answer, Enter for next.

Answers to the starter quiz

Spoilers! These are the Starter quiz’s answers. Easy, Medium, Hard and Mixed rounds show their own answers when you finish.

  1. If + means ×, × means −, − means ÷ and ÷ means +, find the value of 18 − 6 + 4 ÷ 3 × 5.

    • 12
    • 8
    • 10
    • 14

    Answer: 10. Substitute first: 18 ÷ 6 × 4 + 3 − 5. Then BODMAS: 3 × 4 = 12, and 12 + 3 − 5 = 10.

  2. If P means +, Q means −, R means × and S means ÷, find 24 S 4 P 6 R 3 Q 5.

    • 19
    • 21
    • 17
    • 13

    Answer: 19. It becomes 24 ÷ 4 + 6 × 3 − 5 = 6 + 18 − 5 = 19.

  3. Which two signs must be interchanged to make this equation correct? 16 × 4 + 3 ÷ 2 − 5 = 5

    • + and −
    • × and +
    • ÷ and −
    • × and ÷

    Answer: × and ÷. Swapping × and ÷ gives 16 ÷ 4 + 3 × 2 − 5 = 4 + 6 − 5 = 5. The other swaps give 67.5, 17 and 66.6.

  4. If 3 # 4 = 25 and 5 # 12 = 169, then 6 # 8 = ?

    • 196
    • 100
    • 48
    • 14

    Answer: 100. a # b = a² + b²: 9 + 16 = 25 and 25 + 144 = 169. So 36 + 64 = 100.

  5. If 7 $ 3 = 46 and 5 $ 2 = 23, then 9 $ 4 = ?

    • 81
    • 85
    • 77
    • 72

    Answer: 77. a $ b = a² − b: 49 − 3 = 46 and 25 − 2 = 23. So 81 − 4 = 77.

  6. If '×' means addition, '÷' means subtraction, '+' means multiplication and '−' means division, find 20 × 8 ÷ 8 − 4 + 2.

    • 24
    • 26
    • 20
    • 28

    Answer: 24. It becomes 20 + 8 − 8 ÷ 4 × 2. Division and multiplication first: 8 ÷ 4 × 2 = 4. Then 20 + 8 − 4 = 24.

  7. Choose the signs, in order, to fill the blanks: 12 _ 4 _ 3 _ 5 = 4

    • ×, ÷, −
    • ÷, +, −
    • −, ×, ÷
    • ÷, ×, −

    Answer: ÷, ×, −. 12 ÷ 4 × 3 − 5 = 9 − 5 = 4. The others give 11, 1 and 9.6.

  8. If 4 → 18 and 6 → 38 under the same rule, then 9 → ?

    • 81
    • 83
    • 85
    • 79

    Answer: 83. The rule is n² + 2: 16 + 2 = 18 and 36 + 2 = 38. So 81 + 2 = 83.

  9. If 2 @ 3 = 10 and 4 @ 5 = 36, then 6 @ 7 = ?

    • 91
    • 84
    • 72
    • 78

    Answer: 78. a @ b = a × (a + b): 2 × 5 = 10 and 4 × 9 = 36. So 6 × 13 = 78.

  10. If 'A' means '÷', 'B' means '+', 'C' means '×' and 'D' means '−', find 36 A 6 C 3 B 4 D 2.

    • 18
    • 22
    • 20
    • 16

    Answer: 20. It becomes 36 ÷ 6 × 3 + 4 − 2. Left to right for ÷ and ×: 6 × 3 = 18. Then 18 + 4 − 2 = 20.