1)7/8-(-3/10)=7/8+3/10=35/40+12/40=47/40=1 7/40
2)11/12-17/18=33/36-34/36=-1/36
3)-3/7-9/14=-6/14-9/14=-15/14=-1 1/14
4)-5/9 -(-3/4)=-5/9+3/4=-20/36+27/36=7/36
5)3 11/12-(4 4/9)=3 11/12-4 4/9=3 33/36-4 16/36=33/36-1 16/36=17/36-1=19/36
6)4 5/17-6=5/17-2=-1 12/17
7)1 3/8-3 1/4=1 3/8-3 2/8=3/8-2 2/8=1/8-2=-1 7/8
8)-2 14/15-1 19/45=-2 42/45-1 19/45=-3 61/45=-4 16/45
9)-3 1/6-(1 1/4)=-3 1/6-1 1/4=-3 2/12-1 3/12=-4 5/12
А) 86+5=91
(91+85) • 2= 372
в)372 • 4 = 1308
<span>(5 / 14 + 10 / 21) × 18 / 10 + 7 / 6 / (13 / 22 – 25 / 33) = (15/42 + 20/42) * 18/10 + 7/6 : (39/66 - 50/66) = 35/42 * 18/10 + 7/6 : (-11/66) = 7/7 * 3/2 + 7/6 * (-66/11) = 21/14 + 7/1 * (-11/11) = 3/2 + (-7) = 3/2 + (- 14/2) = - 11/2 = - 5,5</span>