Show how to solve 6/15=2/?

There are two way sof doing this question:

1st solution is:

6/15 = 2/5

because 6/15 is divisible by 3 and it is done by this form:

3 X 2 = 6

and

3 X 5 = 15

2nd solution is:

6/15 = 2/?

here we suppose that the missing value is x:

6/15 = 2/x

you shift the denominators and then multiply them by the their numerators:

6 * x = 15 * 2

6x = 30

now you divide 6 on both sides :

6x/6 = 30/6

x = 5

6 / 15 = 2 / x

6x = 30

x = 30 / 6 = 5