А)141-59 <88
141-59=82
б)16<4*8<13*3
4*8=32
13*3=39
16<32<39
4м > 8дм
5м>4м>23дм я думаю так
1/7 + 2/7 + 4/7 = ( 1 + 2 + 4 ) / 7 = 7/7 = 1
a/5 + b/5 + c/5 = ( a + b + c ) / 5
5,6*60:140=2,4(м)
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1) 1-2/9=9/9-2/9=7/9
2) 5+3/10=4 10/10+ 3/10=7 13/10=8 3/10
3)6 7/13-1 2/13=5 5/13
4) 10 2/3-5 2/5=10-5=5, 2/3-2/5=10/15-6/15=5 4/15
5) 5 4/9+1 3/7=5+1=6, 4/9+3/7=28/63+27/63=5 55/63