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Lesson 12 of 15

4 min

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Four questions. Try each one.

20 = 2 × 2 × 5 and 50 = 2 × 5 × 5. What is the HCF of 20 and 50?

Two lamps blink together now. Then one blinks every 10 seconds, the other every 15. When do they blink together again?

The HCF of two numbers is 1. Which pair could they be?

The HCF of 8 and 20 is 4. Their LCM is 40. What is HCF × LCM?

0 of 4 answered

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