Is 400 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 400 is composite or not first we have to find its factors.
Contents
Factors of 400:
- If we have taken numbers from 1, 2, 3…for checking factors of 400, we found that 400 has factors 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400. Hence, we must say that 400 is a composite number.
- Thus, 400 is the composite umber.
- If we multiply 400 by 1, 2, 3 then we get the multiples of 400 which are 400, 800 and so on.
About the number 400:
- 400 has more than two factors which are 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400 and hence it is the composite number.
- 400 is the even composite number and it is the perfect square also.
- If we divide 400 by 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400 then we get remainder as zero. Hence, 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400 are the factors of 400.
Note:
- 400 is the perfect square.
- Factors of 400: 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400
- Prime factors of 400: 2, 5
Conclusion:
- 400 is the composite number which has factors 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400
- And hence, 400 is not the prime number.
Multiple Choice Questions:
1) 400 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 400 are
a) 2
b) 2, 5
c) 1, 4, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400
d) 1, 4, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400
Ans: c) 1, 4, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200 and 400
3) 400 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