Is 87 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 87 is composite or not first we have to find its factors.
Factors of 87:
- If we have taken numbers from 1, 2, 3…for checking factors of 87, we found that 87 has factors 1, 3, 29 and 87. Hence, we must say that 87 is a composite number.
- Thus, 87 is the composite number.
- If we multiply 87 by 1, 2, 3 then we get the multiples of 87 which are 87, 174, and so on.
About the number 87:
- 87 has more than two factors which are 1,3, 29and 87 and hence it is the composite number.
- 87 is the odd composite number and it is not the perfect square also.
- If we divide 87 by 1, 3, 29 and 87 then we get remainder as zero. Hence, 1, 3, 29 and 87 are the factors of 87.
Note:
- 87 is not the perfect square.
- Factors of 87: 1, 3, 29 and 87
- Prime factors of 87: 3, 29
Conclusion:
- 87 is the composite number which has factors 1, 3, 29and 87.
- And hence, 87 is not the prime number.
Multiple Choice Questions:
1) 87 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 87 are
a) 1
b) 3, 29
c) Both a and b
d) 871
Ans: b) 3, 29
3) 1 is the not prime factor of 87 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