Question

factoring numbers up to 50
example: the factors of 18 are 1, 2, 3, 6, 9 and 18
list the factors for each number.

1. 20
2. 26
3. 49
4. 42
5. 5
6. 44
7. 24
8. 9
9. 6
10. 48
11. 28
12. 4
13. 8
14. 35
15. 30
16. 7
17. 40
18. 38
19. 50
20. 13

Explanation:

1. Number 20

Step1: Start from 1

Check if 1 divides 20. $20\div1 = 20$, so 1 and 20 are factors.

Step2: Check 2

$20\div2 = 10$, so 2 and 10 are factors.

Step3: Check 3

$20\div3\approx6.67$ (not integer), so 3 is not a factor.

Step4: Check 4

$20\div4 = 5$, so 4 and 5 are factors.

Step5: Check 5

Already found from step 4. Stop as we pass the square root of 20 (≈4.47).

Step1: Start with 1

$26\div1 = 26$, so 1 and 26 are factors.

Step2: Check 2

$26\div2 = 13$, so 2 and 13 are factors.

Step3: Check 3

$26\div3\approx8.67$ (not integer), stop (√26≈5.1).

Step1: Start with 1

$49\div1 = 49$, so 1 and 49 are factors.

Step2: Check 2

$49\div2 = 24.5$ (not integer).

Step3: Check 3

$49\div3\approx16.33$ (not integer).

Step4: Check 4

$49\div4 = 12.25$ (not integer).

Step5: Check 5

$49\div5 = 9.8$ (not integer).

Step6: Check 6

$49\div6\approx8.17$ (not integer).

Step7: Check 7

$49\div7 = 7$, so 7 is a factor. Stop (√49 = 7).

Answer:

1, 2, 4, 5, 10, 20

2. Number 26