Question

1. Используя свойства дробей, вычислить рациональным способом. 3.4.2 2² 3,8 1 7 a) 1 1 3 1.7-5 4 7 1 3 6) 5 2 1 1.9 2 9 5 7​

Answer 1

Пошаговое объяснение:

а)

(1 1/3 * 3,4 * 2 4/7)/(1 2/7 * 1,7 * 5 1/3) =

(4/3 * 3,4 * 18/7)/(9/7 * 1,7 * 16/3) =

(4/3 * 2 * 18/7)/(9/7 * 1 * 16/3) = (8/3 * 18/7)/(9/7 * 16/3) =

(8/1 * 6/7)/(3/7 * 16/1) = 48/7 / 48/7 = 1

б)

(2 2/7 * 3,8 * 1 1/5)/(1,9 * 2 2/5 * 9 1/7) =

(16/7 * 2 * 6/5)/(1 * 12/5 * 64/7) =

(16/7 * 12/5)/(12/5 * 64/7) = 16/7 / 64/7 =

16/7 * 7/64 = 16/64 = 1/4

Answer 2

$\displaystyle \frac{1\frac{1}{3}\cdot3,4\cdot 2\frac{4}{7}}{1\frac{2}{7}\cdot 1,7\cdot5\frac{1}{3}}=\frac{\frac{4}{_1\not3}\cdot 2\cdot \frac{\not18^6}{7}}{\frac{\not9^3}{7}\cdot 1\cdot\frac{48}{\not3_1}}=\frac{\frac{48}{7}}{\frac{48}{7}}=1$

$\displaystyle \frac{2\frac{2}{7}\cdot3,8\cdot 1\frac{1}{5}}{1,9\cdot 2\frac{2}{5}\cdot9\frac{1}{7}}=\frac{\frac{16}{7}\cdot2\cdot \frac{6}{5}}{1\cdot \frac{12}{5}\cdot\frac{64}{7}}=\frac{\frac{16}{7}\cdot \frac{12}{5}}{\frac{12}{5}\cdot\frac{64}{7}}=\frac{\frac{16}{7}}{\frac{64}{7}}=\frac{16}{7}:\frac{64}{7}=\frac{^1\not16}{_1\not7}\cdot \frac{\not7^1}{\not64_4}=\frac{1}{4}$