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Earn 100

The numbers 49, 81 are _____ numbers.

Important Questions on Prime Time

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Consider the pairs of prime numbers (m, n) between 50 and 100 such that m-n=6. How many such pairs are there?
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Find the mean of the first 6 prime numbers.
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The sum of the squares of the digits of the largest two-digit prime number is:
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One fourth of the sum of the prime numbers, greater than 4 but less than 16, is the square of
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The number of prime numbers which are less than 100 is:
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Which of the following is not a pair of prime numbers ?
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Which of the following number is an odd and prime number?
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Write seven consecutive composite numbers less than 100 having no prime number between them.
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Make a list of seven consecutive numbers, none of which is prime.
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Check whether the given number is prime or not.
 103

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Answer in one Word or a Line

Are two co-prime numbers always prime? is the converse true?
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Following pair of numbers are co-prime?

13 and 16

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Check whether the given number is prime or not.

87

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Sum of the number of primes between 16 to 80 and 90 to 100 is:
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What are composite numbers? Can a composite number be odd? If yes, write the smallest odd composite number.
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What are prime numbers? Give ten examples.
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What are twin primes? Write all the pairs of twin primes between 50 and 100.
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Express the following odd number as the sum of three odd prime numbers.
31
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Express the following number as the sum of twin primes.

36

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What are co-primes? Give examples of five pairs of co-primes. Are co-primes always primes? If no, illustrate your answer by an example.