871.
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2.4=8
8.2=16
3.4=12
12.2=24
2.3=6
6.2=12
16+24+12=52սմ2
52սմ2
873.
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876.
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2.2=4
2.2=4
2.2=4
4+4+4=12
3.3=9
3.3=9
3.3=9
9+9+9=27
27-12=15
15սմ
877.
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3.1=3
6.3=18
1.6=6
3+18+6=27
2.5=10
4.2=8
5.4=20
10+20+8=38
27 < 38
885.
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6:2=3
6+3=9
9
888.
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90:2=45
45=1/5
45.5=225