1/4 of a bucket 6 times:
We have to multiply the amount of concrete (1/4) by the number of times:
Total AMount of concrete = 1/4 x 6 = 6/4 = 3/2 of a bucket of concrete
Then he removes 1/8 of a bucket 2 times
1/8 x 2 = 2/8 = 1/4 of a bucket of concrete
finally, subtract:
3/2-1/4 =
Multiply 3/2 by 2/2:
6/4-1/4 = 5/4 of a bucket of concrete