Is 45 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 45 is composite or not first we have to find its factors.
Factors of 45:
- If we have taken numbers from 1, 2, 3…for checking factors of 45, we found that 45 has factors 1, 3, 5, 9, 15 and 45. Hence, we must say that 45 is a composite number.
- Thus, 45 is the composite number.
- If we multiply 45 by 1, 2, 3 then we get the multiples of 45 which are 45, 90, and so on.
About the number 45:
- 45 has more than two factors which are 1,3, 5, 9, 15and 45 and hence it is the composite number.
- 45 is the odd composite number and it is not the perfect square also.
- If we divide 45 by 1, 3, 5, 9, 15 and 45 then we get remainder as zero. Hence, 1, 3, 5, 9, 15 and 45 are the factors of 45.
Note:
- 45 is not the perfect square.
- Factors of 45: 1, 3, 5, 9, 15 and 45
- Prime factors of 45: 3, 5
Conclusion:
- 45 is the composite number which has factors 1, 3, 5, 9, 15and 45.
- And hence, 45 is not the prime number.
Multiple Choice Questions:
1) 45 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 45 are
a) 1
b) 3, 5
c) Both a and b
d) 451
Ans: b) 3, 5
3) 1 is the not prime factor of 45 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
