Решение по действиям:
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1) 5/4 * 6/5 * 1/6 * 8/7 * 9/8 = 9/28
2) 9/28 - 1/4 = 9/28 - 7/28 = 2/28 = 1/14
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1) 5/2 * 7/5 * 9/7 * 11/9 * 13/11 = 13/2
2) 13/2 + 1/2 = 14/2 = 7
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1) 7/3 * 8/7 * 15/11 * 19/15 * 23/19 = (8*23)/(3*11) = 184/33
2) 184/33 - 2/3 = 184/33 - 22/33 = 162/33 = 4 30/33 = 4 10/11