А) b + 5 9\10 = 7 5\12
b=89\12-59\10
b=445\60-354\60
b=91\60
b=1 31\60
<span>б) 3,85 x (d - 4,02) = 8,47
</span>d-4.02=8.47:3.85
d-4.02=2.2
d=2.2+4.02
d=6.22
2*12/132 - 1*11/132= 24/132-11/132=13/132
4/9 / 2 = 2/9
5/7 / 3 = 5/21
10/21 / 5 = 2/21
9/10 / 15 = 3/50
3/7 / 21 = 1/49