Wykonajmy obliczenia.

N.

$1-2,25:0,9=1-22,5:9=1-2,5=-1,5$

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T.

$1,5+{\left(-1\frac{1}{2}\right)}^2=1,5+\left(-1,5\right)\cdot \left(-1,5\right)=1,5+2,25=3,75$

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R.

$10-0,2\cdot 20=10-4=6$

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I.

$\frac{1}{5}\cdot \left(3\frac{1}{8}+0,625\right)=\frac{1}{5}\cdot \left(3,125+0,625\right)=\frac{1}{5}\cdot 3\frac{3}{4}=\frac{1}{{\cancel{5}}_1}\cdot \frac{{\cancel{15}}^3}{4}=\frac{3}{4}$

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A.

$5,7-{\left(1,1\right)}^2=5,7-1,1\cdot 1,1=5,1-1,21=4,89$

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L.

$-1,5+3\cdot \left(-2,5\right)=-1,5-7,5=-9$

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O.

$-\frac{3}{4}\cdot \left(-0,16\right)+1\frac{1}{10}\cdot \left(-0,3\right)=\frac{3}{{\cancel{4}}_1}\cdot \left(-\frac{{\cancel{16}}^4}{100}\right)+1,1\cdot \left(-0,3\right)=$

$=-\frac{12}{100}-0,33=-0,12-0,33=-0,45$

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A.

$\frac{1}{2}\cdot 2,5-7\frac{3}{4}:2=\frac{1}{2}\cdot \frac{5}{2}-\frac{31}{4}\cdot \frac{1}{2}=$

$=\frac{5}{4}-\frac{31}{8}=\frac{10}{8}-\frac{31}{8}=$

$=-\frac{21}{8}=-2\frac{5}{8}$

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Uszeregujmy wyniki malejąco:

$6>4,89>3,75>-0,45>-1,5>-2\frac{5}{8}>-9$

Hasło: RATIONAL