Prime and Composite Numbers

IMPORTANT

Prime and Composite Numbers: Overview

This topic covers concepts such as Sieve of Eratosthenes Method to Find Prime Numbers, Prime and Composite Numbers, Prime Numbers, Composite Numbers, Smallest Prime and Composite Numbers, Basic Properties of Prime Numbers, etc.

Important Questions on Prime and Composite Numbers

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The following grid shows the multiples of the number from 1 to 10.

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The multiples of 3 are blue cells.

Note down the multiples of 3.

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The following grid shows the multiples of the number from 1 to 10.

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The multiples of 2 are red cells.

Note down the multiples of 2.

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Write down those numbers which have exactly two factors.

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Is there a number which is not a factor of itself?

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Which is the prime number nearest to 35?

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Write the composite numbers between 1 and 10.

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Write the prime numbers less than 4.

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Write the prime numbers between 4 and 10.

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Circle the prime numbers.

12, 22, 15, 23, 17, 25, 21, 19, 20, 35

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Express 12 as sum of the two odd prime numbers and write the smallest odd prime number as the final answer.

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There are four prime numbers written in ascending order. The product of the first three is 385 and that of the last three is 1001. The first prime number is:

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Write a pair of prime numbers whose difference is 1.

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Is 1 a composite number?

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Is 1 a prime number ?

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28 is a composite number.

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25 is a prime number.

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1 is the smallest prime number.

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Since 18 has 6 factors, 18 is a _____ number.

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Every prime number except _____ is odd.

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Name two composite numbers with same digits like 26 and 62.