计算（能简算的要简算） 15/16-(2/3+1/4) 1/4-7/12+3/4-5/12

15/16-(2/3+1/4)
=15/16-(8/12+3/12)
=15/16-11/12
=1/12-1/16
=1/48
1/4-7/12+3/4-5/12
=(1/4+3/4)-(7/12+5/12)
=1-1
=0