Answer :
First you do 1.72/80 times 100. So you reduce 80 to 4 and 100 to 5. Then you reduce 1.72/4 to 43. Multiply numerator times numerator and denominator time denominator and you would get 2.15 so 2.15 is your answer.
Divide 1.72 by 80 then multiply by 100 it's that simple ( 1.72/80= 0.0215* 100 = 2.15. Try the others using the same system.
