5 2/5 - 9 1/5 lets say its $5.40 and you also have $9.20. 5.40 would be 5 40/100 since it take 100 cents to make a dollar. you would round it down to the smallest it can go like so
40/100 divide them both by 10 because 10 is the greatest common factor to get 4/10 then you would round it down again because 2 can go into it so it would be 2/5 because 2 times 2 is four and 2 times five is 10. you basically do the same thing on every problem. Highest common factor and round it down until you can't anymore
