3*4=12 см, т.к. между 5-ю фишками 4 промежутка по 3 см
4/15 не сокращается
6/15 = 2/5
4/10 = 2/5
10/25 = 2/5
14/30 = 7/15
18/45 = 2/5
<span>(4 * 5/6 - 2,5) *12 - 27 * 5/9 = - 5
1. 4 * 5/6 = 10/3 = 3 1/3
2. 3 1/3 - 2.5 = 3 1/3 - 2 1/2 = 10/3 - 5/2 = 20/6 - 15/6 = 5/6
3. 5/6 * 12 = 5 * 2 = 10
4. 27 * 5/9 = 3 * 5 = 15
5. 10 - 15 = - 5
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