Question

25c+23c-715c=2 12

Answer 1

/-дробная черта 2/5c+2/3c-7/15c=2 1/2;
9/15с=5/2;
3/5с=5/2;
6=25с
25с=6
С=6/25=0.4

Answer 2

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Answer 3

С=5/3