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Primes, HCF and LCM - Prime Numbers and Composite Numbers

Primes, HCF and LCM - Prime Numbers and Composite Numbers

Secondary 1

  1. \(p\) and \(q\) are prime numbers, \(p<q\), and \(pq=91\). Find \(p\) and \(q\).

  2. A two-digit prime has digits with sum \(10\). Its tens digit is \(4\) less than its units digit. Find the number, then decide whether reversing its digits also gives a prime.

Solution:

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Answer:(a) \(p=7,\ q=13 \) (b) \(37\) (Prime); \(73\) (Prime)

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