64:8 равно 8. 8умножить на 3 равно 24 64+8+24 рав но 96
-3,1-x=0.9
-x=0.9+3.1
-x=4
x=-4
А) 3 2/15 х + 1 7/10 х = 9 2/3
47/15х + 17/10х = 29/3
470/150х + 255/150х = 29/3
725/150х = 29/3
145/30х = 29/3
29/6 х = 29/3
х = 29/3 : 29/6
х = 29/3 * 6/29
х = 6/3
х = 2
б) (х - 3/8х) * 2 4/5 - 1 3/14 = 2 2/7
(х - 3/8х) * 14/5 - 17/14 = 16/7
(х - 3/8х) * 14/5 = 16/7 + 17/14
(х - 3/8х) * 14/5 = 32/14 + 17/14
(х - 3/8х) * 14/5 = 49/14
(х - 3/8х) * 14/5 = 7/2
х - 3/8х = 7/2 : 14/5
х - 3/8х = 7/2 * 5/14
х - 3/8х = 1/2 * 5/2
х - 3/8х = 5/4
1/1х - 3/8х = 5/4
8/8х - 3/8х = 5/4
5/8х = 5/4
х = 5/4 : 5/8
х = 5/4 * 8/5
х = 8/4
х = 2
2/5=0.4
(0.4-1.7)*(-3)=3.9
1)0.4-1.7=-1.3
2)(-1.3)*(-3)=3.9
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