Решите уравнения (1/3 х+1/6 х) •2/21=1/3 (7/15 х-1/3 х) : 1/5+1/3=4

№1

(1/3 х + 1/6 х) * 2/21 = 1/3;

(2/6 х + 1/6 х) * 2/21 = 1/3;

3/6 х * 2/21 = 1/3;

3/6 х = 1/3 : 2/21;

3/6 х = 1/3 * 21/2;

3/6 х = 7/2;

х = 7/2 : 1/2;

х = 7/2 * 2/1;

х = 7.

Ответ: х = 7.

№2

(7/15 х - 1/3 х) : 1/5 + 1/3 = 4;

(7/15 х - 5/15 х) : 1/5 + 1/3 = 4;

2/15 х: 1/5 + 1/3 = 4;

2/15 х: 1/5 = 4 - 1/3;

2/15 х: 1/5 = 12/3 - 1/3;

2/15 х: 1/5 = 11/3;

2/15 х = 11/3 * 1/5;

2/15 х = 11/15;

х = 11/15 : 2/15;

х = 11/15 * 15/2;

х = 11/2 = 5 1/2.

Ответ: х = 11/2 = 5 1/2.