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21 is divisible by 3 and 7, so it is composite. 91 is divisible by 7 and 13, so it is composite. 51 is divisible by 3 and 17. 31 is divisible by only 1 and itself, so it is the Prime number.
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Earn +20 ptsQ: Which number is prime out of 91 51 31 21?
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Related questions
Which of 21 31 51 and 91 is a prime number?
31 is a prime number.
Which number is a prime 91 51 31 or 21?
31
Which is a prime number 91 51 31 21?
31
Which number is prime 91 51 31 21?
31
What number is a prime number 91 51 31 21?
31 is the only one that has only two factors: 1 and itself. It is the prime number.
Which is not a prime number 17 23 31 or 51?
51 is not a prime number: 3x17=51
What is a prime number 17 23 31 51?
51 is composite number
Which number is a prime number a.91 b.51 c.31 d. 21?
91 = 13*751 = 17*321 = 3*731 is prime. â–
Which number is a composite number 51 41 31 11?
51 is composite.
Are 31 and 51 prime numbers?
31 is prime, but 51 is not as 51=3*17.
Are 40 and 51 relativly prime?
51 is not a prime number. It is divisible by 3.
Which is not a prime number between 17 23 31 and 51?
51 = 3 x 17
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