Is 91 is a composite number or not ?
- As we already know that, the number having factors 1 and the number itself is the prime number.
- And numbers having more than these two factors are the composite numbers.
- To check whether the number 91 is composite or not first we have to find its factors.
Contents
Factors of 91:
- If we have taken numbers from 1, 2, 3…for checking factors of 91, we found that 91 has factors 1, 7, 13 and 91. Hence, we must say that 91 is a composite number.
- Thus, 91 is the composite number.
- If we multiply 91 by 1, 2, 3 then we get the multiples of 91 which are 91, 182, and so on.
About the number 91:
- 91 has more than two factors which are 1,7, 13and 91 and hence it is the composite number.
- 91 is the odd composite number and it is not the perfect square also.
- If we divide 91 by1,7, 13 and 91 then we get remainder as zero. Hence, 1, 7, 13 and 91 are the factors of 91.
Note:
- 91 is not the perfect square.
- Factors of 91: 1, 7, 13 and 91
- Prime factors of 91: 7, 13
Conclusion:
- 91 is the composite number which has factors 1, 7, 13and 91.
- And hence, 91 is not the prime number.
Multiple Choice Questions:
1) 91 is a
a) odd number
b) Prime number
c) Composite number
d) Both a and c
Ans: d) both a and c
2) The prime factors of a composite number 91 are
a) 1
b) 7, 13
c) Both a and b
d) 911
Ans: b) 7, 13
3) 1 is the not prime factor of 91 because
a) It is the prime number
b) 1 is neither prime nor composite number
c) Both a and b
d) Given statement is false
Ans: b) 1 is neither prime nor composite number