А)15-(6-4)=13
1)6-4=2
2)15-2=13
Б)16+(9-7)=18
1)9-7=2
2)16+2=18
С= 2πr = 2 • 4.5 • π = 9π см или 28.26см
<span>а)3 1/9-(3.5+2 1/9) = </span><span>-2 1/2
3,5 + 2 1/9= 3 5/10 + 2 1/9 = 5 + (5/10+1/9) = 5 +(1/2+1/9)= 5 + (9/18+2/18)= 5 11/18
3 1/9 - 5 11/18 = 3 2/18 - 5 11/18= -2 9/18= -2 1/2
б)1 5/14-(1 2/7-2 9/14)</span> = <span>2 5/7</span>
<span>1 2/7-2 9/14 = 1 4/14 - 2 9/14 = - 1 5/14
1 5/14 - (-1 5/14) = 1 5/14 + 1 5/14 = 2 10/14= 2 5/7
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Цыпленок-слово исключение
цитата