Factor the following integer:
40
The last digit of 40 is 0, which means it is even. Therefore 40 is divisible by 2:
40 = 2 20:
40 = 2×20
The last digit of 20 is 0, which means it is even. Therefore 20 is divisible by 2:
20 = 2 10:
40 = 2×2×10
The last digit of 10 is 0, which means it is even. Therefore 10 is divisible by 2:
10 = 2 5:
40 = 2×2×2×5
5 is not divisible by 2 since 5 is odd and 2 is even:
40 = 2×2×2×5 (5 is not divisible by 2)
Divide 3 into 5:
| 1 | (quotient)
3 | 5 |
- | 3 |
| 2 | (remainder)
5 is not divisible by 3:
40 = 2×2×2×5 (5 is not divisible by 2 or 3)
No primes less than 5 divide into it. Therefore 5 is prime:
40 = 2×2×2×5
There are 3 copies of 2 and 1 copy of 5 in the product:
Answer: 40 = 2^3×5