1.
a) 4 1/6 * 2 2/5 = 25/6 * 12/5 = 10
б) 2 1/10 * 2 1/7 = 21/10 * 15/7 = 9/2 = 4 1/2
в) 1 7/8 * 2 2/5 = 15/8 * 12/5 = 9/2 = 4 1/2
г) 2 2/21 * 3 1/2 = 44/21 * 7/2 = 22/3 = 7 1/3
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2.
3 1/8 * 1 2/5 * 1 3/5 = 25/8 * 7/5 * 8/5 = 7 дм.
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3.
а) (4 1/12 * 1 5/7 - 5 2/9) * 3/8
1) 4 1/12 * 1 5/7 = 49/12 * 12/7 = 7
2) 7 - 5 2/9 = 6 9/9 - 5 2/9 = 1 7/9
3) 1 7/9 * 3/8 = 16/9 * 3/8 = 2/3
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б) (3/8 + 2 1/7 * 1 1/20) * 1 1/3
1) 2 1/7 * 1 1/20 = 15/7 * 21/20 = 3/4
2) 3/8 + 3/4 = 3/8 + 6/8 = 9/8
3) 9/8 * 1 1/3 = 9/8 * 4/3 = 3/2 = 1 1/2