Last winter armand had 5/6 of a row of stacked logs. at the end of the winter he had 8/15 of the same row left. how much wood did he burn over the winter?
1 9/16 rows
1 11/30 rows
4/9 row
3/10 row

First we have to make the fractions even so there denominator have to be equal. So 15 times 2 gets 30 and 6 times 5 gets 30 too. Ok now multiply the nominator by the corresponding number of 25/30 and 16/30. Subtract to get 9/30 now simplify to get 3/10.