Answer :
It's easier to figure it out when both fractions have the same denominator, so let's fix that:
17/40*15/15 is 255/600
8/15*40/40 is 320/600
Notice we are multiplying by a factor of 1 to get equivalent fractions
So 8/15 is bigger
Hope this helped!
8/15
when you divide it it comes out to be 0.533 repeating
but when you divide 17/40 it comes out to be 0.425
so .5 is larger then .4