1) 4x - 5 1/3y
4 * 5/9 - 16/3 * 3/16 = 20/9 - 1 = 2 2/9 - 1 = 1 2/9
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2) 61/8 : z
61/8 : 7/20 = 305/14 = 21 11/14
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1 2/9 + 21 11/14 - 17 1/2 = 1 2/9 + 21 11/14 - 17 7/14 = 1 2/9 + 4 4/14 =
= 1 2/9 + 4 2/7 = 1 14/63 + 4 18/63 = 5 32/63