7 целых 13/15 и теперь находи процент
1) 200÷20=10(м) ширина зала
2) (10+20)×2=60(м) периметр зала
Z + 2 11/15 = 7 5/39
z = 7 5/39 - 2 11/52
z = 278/39 - 115/52 = 767/156
z = 4 143/156 = 4 11/12
6 3/7+(х- 3 5/7) = 9
6 3/7+х- 3 5/7 = 9
х+5 10/7- 3 5/7 = 9
<span>х+2 5/7 = 9
</span><span>х = 9-2 5/7
х=7 -5/7
х=6 7/7-5/7
х=6 2/7
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