so this wants you to add the fractions and subtract 1/1
we know that 6/8=3/4 because 3/4 times 2/2 (or 1) os 6/8
so we need the denomenators (bottom number) to be the same
so 5/6=10/12
1/4=3/12
2/3=8/12
add them together
10+3+8=21
21/12=1 and 9/12
subtract 1 and get
9/12 left or 3/4 yard left