0580/23 May/Jun 2025, Question 8: Prime Factorization
Cambridge IGCSE Mathematics 0580 · Paper 23 (Extended) · Non-calculator · 4 marks
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The question, in short
Write 42 as a product of primes, then find the highest common factor of 84 and 70.
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Part (a) · 2 marks
Express 42 as a product of its prime factors.
- 142 ÷ 2 = 21
- 221 ÷ 3 = 7, and 7 is prime
- 342 = 2 × 3 × 7
Answer2 × 3 × 7
Part (b) · 2 marks
Find the HCF of 84 and 70.
- 184 = 2 × 2 × 3 × 7
- 270 = 2 × 5 × 7
- 3HCF = 2 × 7 = 14
Answer14
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Also searched as: 0580/23/M/J/25 · 0580_s25_qp_23 · 0580 s25 23 · question 8.
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