Question

Question 11 Write five pairs of prime numbers less than 20 whose sum is divisible by 5. (Hint: 3 + 7 = 10)

Class 6 - Math - Playing with Numbers Page 54

Answer 1

Hi ,

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Prime numbers :

Any natural number which has only

two factors i.e 1 and itself is called

a prime number.

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Prime numbers less than 20 are

2 , 3 , 5 , 7 , 11 , 13 , 17 , 19

According to the problem given ,

Pair of prime numbers less than 20

whose

sum is divisible by 5

1 ) ( 2 , 3 )

2 ) ( 3 , 7 )

3 ) ( 7 , 13 )

4 ) ( 2 , 13 )

5 ) ( 13 , 17 )

I hope this helps you.

: )

Answer 2

Prime numbers under 20 are

• 2, 3, 5, 7, 11, 13, 17, 19



Required pairs are

• 2, 3
• 3, 7
• 7, 11
• 3, 17
• 13, 17



I hope this will help you

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