Tính biểu thức

bài 3:
a) M=-5/7.2/11+-5/7.9/11+1/5/7
b) N=-3/7.5/9+4/9.-3/7+2/3/7
c) P=-7/8.5/9-4/9.7/8+5/7/8
d) Q=-4/9.7/15+4/-9.8/15
e) T=5/-4.16/25+-5/4.9/25
bài 4:
a) 4/11/23-9/14+2/12/23-5/14
b) 2/13/17-7/15+3/14/27-8/15
c) 11/1/4-(2/5/7+5/1/4)
d)1/2+3/4-(3/4-4/5)
e)49/8/23-(5/7/32+14/8/23)