4) 13 1/5 * 3 2/11 = 66/5 * 35/11 = 42 (правильный ответ под номером 2)
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5) (3,2 * 5 5/6 - 15,4) * 4 2/7
1) 3,2 * 5 5/6 = 3 2/10 * 35/6 = 3 1/5 * 35/6 = 16/5 * 35/6 = 56/3 = 18 2/3
2) 18 2/3 - 15,4 = 18 2/3 - 15 4/10 = 18 2/3 - 15 2/5 = 18 10/15 - 15 6/15 = 3 4/15
3) 3 4/15 * 4 2/7 = 49/15 * 30/7 = 14
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6)
одна сторона = 2 2/9
вторая = 2 2/9 + 1 1/3 = 2 2/9 + 1 3/9 = 3 5/9
Перимерт = 2*(2 2/9+ 3 5/9) = 2* 5 7/9 = 2 * 52/9 = 104/9 = 11 5/9