0580/21 Oct/Nov 2021, Question 1: Prime Numbers
Cambridge IGCSE Mathematics 0580 · Paper 21 (Extended) · Calculator · 2 marks
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The question, in short
Find the prime P between 60 and 80 that is two less than a square number.
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Solution · 2 marks
- 1Square numbers near 60 to 80: 64 and 81
- 264 − 2 = 62 (not prime), 81 − 2 = 79
- 379 is prime, so P = 79
Answer79
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Also searched as: 0580/21/O/N/21 · 0580_w21_qp_21 · 0580 w21 21 · question 1.
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