What is the ratio of 9 to 14 in simplest form?

Answer 1

Basically, to cancel down fractions or ratios, you have to find common factors.

2: No

3: No

4: No

5: No

6: No

7: No

8: No

9: No

There already are in there simplest form

While the above is true, it is a pretty dumb way to do it. If 2 is not a factor then its multiples (4, 6 and 8) are not going to be factors. But every time you do find a factor you have to repeat from that factor onwards. Second, if the square of the prime factor is bigger than the smaller of the two numbers, stop.

So you test 2, test 3. The next Prime number is 5 but 52 = 25 which is bigger than the smaller of the two numbers (9), so don't bother. Only two numbers to check instead of the suggested 8!