Question

To which numbers could you apply cancelling when calculating the product 8/9 x 5/6 ?
8 and 6
9 and 6
8 and 5
5 and 9

Answer 1

do you know how to find prime factors?
im assuming thats what your question is refering to

Answer 2

You can only apply cancelling to a pair of numbers, one in the nominator part, one in the denominator part, where both numbers can divided by the same number. In this case: 8 and 6.