Question

помагитееее пж дам 50 баллов ​

Answer 1

Ответ:

Пошаговое объяснение:

(2/21 + 5/21) + 2/3 = 1

1) 2/21 + 5/21 = 7/21 = 1/3

2) 1/3 + 2/3 = 3/3 = 1

(5/30 + 1/30) - (5/20 - 1/20) = 0

1) 5/30 + 1/30 = 6/30 = 1/5

2) 5/20 - 1/20 = 4/20 = 1/5

3) 1/5 - 1/5 = 0

Answer 2

Пошаговое объяснение:

1.

$( \frac{2}{21} + \frac{5}{21} ) + \frac{2}{3} = \frac{7}{21} + \frac{2}{3} = \frac{1}{3} + \frac{2}{3} = 1$

2.

$(\frac{5}{30} + \frac{1}{30} ) - ( \frac{5}{20} - \frac{1}{20} = \frac{6}{30} - \frac{4}{20} = \frac{1}{5} - \frac{1}{5} = 0$