0580/32 Oct/Nov 2024, Question 2: HCF and LCM
Cambridge IGCSE Mathematics 0580 · Paper 32 (Core) · Calculator · 17 marks
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The question, in short
From a list of numbers, identify odd, factor of 28, square, prime, and multiple of 9; then evaluate powers, prime factorisation, cube root, estimation, standard form, and a lap timing problem.
Summarised in our own words. Use the official paper for the exact wording and any diagrams.
Part (ai) · 1 mark
Pick an odd number from the list.
- 141 is a whole number not divisible by 2
- 241 (or 117 or 121)
Answer41 or 117 or 121
Part (aii) · 1 mark
Pick a number from the list that divides 28.
- 128 ÷ 14 = 2
- 214
Answer14
Part (aiii) · 1 mark
Pick a square number from the list.
- 111² = 121
- 2121
Answer121
Part (aiv) · 1 mark
Pick a prime number from the list.
- 141 has no factors other than 1 and 41
- 241
Answer41
Part (av) · 1 mark
Pick a multiple of 9 from the list.
- 19 × 13 = 117
- 2117
Answer117
Part (b) · 1 mark
State the value of 5⁰.
- 1Any non-zero number to the power 0 is 1
- 25⁰ = 1
Answer1
Part (c) · 2 marks
Express 60 as a product of prime factors.
- 160 = 2 × 30
- 230 = 2 × 15
- 315 = 3 × 5
- 460 = 2² × 3 × 5
Answer2 × 2 × 3 × 5 or 2² × 3 × 5
Part (d) · 1 mark
Work out the cube root of 157464.
- 1∛157 464 on the calculator
- 2= 54
Answer54
Part (e) · 2 marks
Round each value to 1 significant figure and estimate (67.8 × 2.38) ÷ (4.803 + 29.87), showing working.
- 167.8 ≈ 70, 2.38 ≈ 2, 4.803 ≈ 5, 29.87 ≈ 30
- 2(70 × 2)/(5 + 30) = 140/35
- 3= 4
Answer4
Part (fi) · 1 mark
Compare 9.78 × 10⁸ and 2.04 × 10⁹, stating which is larger and why.
- 19.78 × 10⁸ = 978 000 000
- 22.04 × 10⁹ = 2 040 000 000
- 32.04 × 10⁹ is larger because it has the larger power of 10
Answer2.04 × 10⁹ and it has the larger power of 10
Part (fii) · 2 marks
Calculate (1.732 × 10³) ÷ (5.73 × 10⁻¹) and give the answer in standard form.
- 11.732 × 10³ = 1732, 5.73 × 10⁻¹ = 0.573
- 21732 ÷ 0.573 = 3022.6…
- 3= 3.02 × 10³
Answer3.02 × 10³ or 3.023 × 10³
Part (g) · 3 marks
Two cars lap in 96 s and 120 s, starting together at 08 37; find the next time they start a lap together.
- 196 = 2⁵ × 3, 120 = 2³ × 3 × 5
- 2LCM = 2⁵ × 3 × 5 = 480 seconds
- 3480 s = 8 minutes
- 408 37 + 8 min = 08 45
Answer08 45
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Also searched as: 0580/32/O/N/24 · 0580_w24_qp_32 · 0580 w24 32 · question 2.
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