Is 408 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 408 is composite or not first we have to find its factors.
Contents
Factors of 408:
- If we have taken numbers from 1, 2, 3…for checking factors of 408, we found that 408 has factors 1, 2, 3, 4, 6, 8, 12, 17, 24, 34, 51, 68, 102, 136, 204 and 408. Hence, we must say that 408 is a composite number.
- Thus, 408 is the composite umber.
- If we multiply 408 by 1, 2, 3 then we get the multiples of 408 which are 408, 816 and so on.
About the number 408:
- 408 has more than two factors which are 1, 2, 3, 4, 6, 8, 12, 17, 24, 34, 51, 68, 102, 136, 204 and 408 and hence it is the composite number.
- 408 is the even composite number and it is not the perfect square also.
- If we divide 408 by 1, 2, 3, 4, 6, 8, 12, 17, 24, 34, 51, 68, 102, 136, 204 and 408 then we get remainder as zero. Hence, 1, 2, 3, 4, 6, 8, 12, 17, 24, 34, 51, 68, 102, 136, 204 and 408 are the factors of 408.
Note:
- 408 is not the perfect square.
- Factors of 408: 1, 2, 3, 4, 6, 8, 12, 17, 24, 34, 51, 68, 102, 136, 204 and 408
- Prime factors of 408: 2, 3, 17
Conclusion:
- 408 is the composite number which has factors 1, 2, 3, 4, 6, 8, 12, 17, 24, 34, 51, 68, 102, 136, 204 and 408
- And hence, 408 is not the prime number.
Multiple Choice Questions:
1) 408 is a
a) Prime number
b) Odd number
c) Composite number
d) Both b and c
Ans: c) composite number
2) The non-prime factors of a composite number 408 are
a) 2
b) 2, 3, 17
c) 1, 4, 6, 8, 12,24, 34, 51, 68, 102, 136, 204 and 408
d) 1, 4, 6, 8, 12, 24, 34, 51, 68, 102, 136, 204 and 408
Ans: c) 1, 4, 6, 8, 12, 24, 34, 51, 68, 102, 136, 204 and 408
3) 408 is the composite number because
a) It has two factors
b) More than two factors
c) Divisible by 2
d) Both b and c
Ans: b) more than two factors