13 over 15
You divide both figures with the same number until one of them is a Prime number. In this case, you're only able to divide by 2. (then 26 is turned into 13, which is a prime number)
26/30 = 13/15 in its lowest terms
30 over 35 in the lowest terms = 6/7
It is already in lowest terms.
12 over 30 in lowest terms is 2/5
15 over 30 reduced to lowest terms is 1/2
24 over 30 written in lowest terms is 4/5
3
It is: 30/70 = 3/7.
It is: 30/40 = 3/4.
It is: 30/36 = 5/6
1/42
10