№ 739
5 1/3 + 2/3 = 5 + (1/3 + 2/3) = 5 + 3/3 = 5 + 1 = 6
5/7 + 1 2/7 = 1 +(5/7 + 2/7) = 1 + 7/7 = 1 + 1 = 2
5 1/5 + 2 4/5 =(5+2)+(1/5+4/5) =7 + 1 = 8
1 3/4+5 1/4 = (1+5) +(3/4+1/4) = 6 + 1 = 7
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№ 740
4/9+2/9+1 = 6/9 +1 = 1 6/9
4/11 +3 +3/11 = 3 7/11
1 5/12 + 1/12 + 1/12 = 1 5/12 + 2/12 = 1 7/12
12 +5/6 +1/6 = 12 + 1 = 13
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№741
3 8/17 + 2 13/17 = (3+2)+(8/17+13/17)= 5 + 21/17 = 6 4/17
6 9/14+2 13/14 = (6+2)+(9/14+13/14) = 8 + 22/14 = 9 8/14
1 5/7 + 1 6/7 = (1+1)+(5/7+6/7)= 2 + 11/7 = 3 4/7
5 7/8 +3 3/8 = (5+3)+(7/8+3/8)= 8 10/8 = 9 2/8