2 9/35 + 1 9/14 = 79/35 + 23/14 = 158/70 + 115/70 = 273/70 = 3 63/70
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4 4/15 + 1 5/6 = 64/15 +11/6 = 128/30 + 55/30 = 183/30 = 6 3/30 = 6 1/10
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4 1/26 - 3 8/39 = 105/26 - 125/39 = 315/78 - 250/78 = 65/78