Решебник по алгебре и начала математического анализа 11 класс Алимов Задание 1218

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$$1)3,8,5,6;$$

$$\bar{X}=\frac{3+8+5+6}{4}=\frac{22}{4}=5,5.$$

$$=\frac{{2,5}^2+{2,5}^2+{0,5}^2+{0,5}^2}{4}=$$

$$=\frac{6,25+6,25+0,25+0,25}{4}=$$

$$=\frac{13}{4}=3,25.$$

$$\sigma =\sqrt{D}=\sqrt{3,25}\approx 1,8.$$

$$2)4,7,3,9;$$

$$\bar{X}=\frac{4+7+3+9}{4}=\frac{23}{4}=5,75.$$

$$=\frac{22,74}{4}\approx 5,68.$$

$$\sigma =\sqrt{D}=\sqrt{5,68}\approx 2,38.$$

$$3)4,1,3,2,2;$$

$$\bar{X}=\frac{4+1+3+2+2}{5}=\frac{12}{5}=$$

$$=2,4.$$

$$=\frac{5,2}{5}=1,04.$$

$$\sigma =\sqrt{D}=\sqrt{1,04}\approx 1,02.$$

$$4)3,2,1,1,5;$$

$$\bar{X}=\frac{3+2+1+1+5}{5}=\frac{12}{5}=$$

$$=2,4.$$

$$=\frac{11,2}{5}=2,24.$$

$$\sigma =\sqrt{D}=\sqrt{2,24}\approx 1,49.$$

$$5)2,-1,3,-2,5;$$

$$\bar{X}=\frac{2-1+3-2+5}{5}=\frac{7}{5}=1,4.$$

$$=\frac{33,2}{5}=6,64.$$

$$\sigma =\sqrt{D}=\sqrt{6,64}\approx 2,57.$$

$$6)-2,4,-3,-1,6;$$

$$\bar{X}=\frac{-2+4-3-1+6}{5}=\frac{4}{5}=$$

$$=0,8.$$

$$=\frac{62,8}{5}=12,56.$$

$$\sigma =\sqrt{D}=\sqrt{12,56}\approx 3,54.$$