1.
а) 3 2/5 - (1 1/3 + 1 1/4)
1. 1 1/3 + 1 1/4 = 4/3 + 5/4 = 16/12 + 15/12 = 31/12
2. 3 2/5 - 31/12 = 17/5 - 31/12 = 204/60 - 155/60 = 49/60
б) 3.4 + 2 3/4 = 3 4/10 + 2 3/4 = 34/10 + 11/4 = 68/20 - 55/20 = 13/20
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2.
x - 2 1/3 = 12 1/4
x = 12 1/4 + 2 1/3 = 12 3/12 + 2 4/12 = 14 7/12
x = 14 7/12
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3.
(3 1/4 - 2 2/3)(1 5/6 - 1 7/12)+ 3 5/24
1) 3 1/4 - 2 2/3 = 13/4 - 8/3 = 39/12 - 32/12 = 7/12
2) 1 5/6 - 1 7/12 = 11/6 - 19/12 = 22/12 - 19/12 = 3/12 = 1/4
3) 7/12 * 1/4 = 7*1 / 12*4 = 7/48
4) 7/48 + 3 5/24 = 7/48 + 77/24 = 7/48 + 154/48 = 161/48 = 3 17/48