Question

64/112=2.8/4 Х-3.1


/-дробная черта

Answer 1

Дано:
64/112 = 2.8/4 Х-3.1
Решение:
64/112 = 16/28(сократим) = 4/7
2,8/4 = 7/10
3,1 = 3 1/10
4/7 = 7/10X - 3 1/10
7/10X = 4/7 + 3 1/10
7/10X = 40/70 + 3 7/70
7/10X = 3 47/70
7/10X = 257/70
X = 257/70 : 7/10 = 257/70 * 10/7=257/7 * 1/7 = 257/49 = 5 12/49