8х = 54
х = 54 : 8
х = 6,75
-3х = 43
х = 43 : (-3)
х = - 14и1/3
-8х=48
х = 48 : (-8)
х = -6
-6х=-23
х = -23 : (-6)
х = 3и5/6
В)12,8*0,25:(0,125-3/4)=3,2:0,625=5,12
1-4-(-5/12)-35/36==1-4+5/12-35/36=-3 5/9
1) 1-4=-3
2) -3+5/12=-2 7/12
3) -2 7/12-35/36=-2 21/36-35/36=-2 56/36=-3 20/36=-3 5/9
(2 3/5-1 7/10)+(1 1/2-7/20) = 6 1/20
1) 2 3/5-1 7/10 = 2 6/10 - 1 7/10= 9/10
2) 1 1/2-7/20 = 110/20 -7/20 = 5 3/20
3) 9/10 + 5 3/20 = 18/20 + 5 3/20 = 5 21/20 = 6 1/20
25*1/5=25/5=5 лет
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