Решите уравнения : 1)4/15-(у+3/25)=1/25 2)(8 целых 3/14-у):3/7=17 3)3 целых 1/16 :(х-5/16) =7/8

 1) 4/15 - (у + 3/25) = 1/25; 

у + 3/25 = 4/15 - 1/25; 

у + 3/25 = (4 * 5)/(15 * 5) - (1 * 3)/(25 * 3); 

у + 3/25 = 20/75 - 3/75; 

у + 3/25 = 17/75; 

у = 17/75 - 3/25; 

у = 17/75 - (3 * 3)/(25 * 3); 

у = 17/75 - 9/75; 

у = 8/75. 

Проверка: 

4/15 - (8/75 + 3/25) = 1/25; 

4/15 - (8/75 + 3/25) = 1/25; 

4/15 - ((8/75 + (3 * 3)/(25 * 3)) = 1/25; 

4/15 - (8/75 + 9/75) = 1/25; 

4/15 - 17/75 = 1/25; 

(4 * 5)/(15 * 5) - 17/75 = 1/25; 

20/75 - 17/75 = 1/25; 

3/75 = 1/75; 

1/75 = 1/75. Решение верно. 

2) (8 3/14 - у) : 3/7 = 17; 

8 3/14 - у = 3/7 * 17; 

115/14 - у = 51/7; 

у = 115/14 - 51/7; 

у = 115/14 - (51 * 2)/(7 * 2); 

у = 115/14 - 102/14; 

у = 13/14. 

Проверка: 

(8 3/14 - 13/14) : 3/7 = 17;

(115/14 - 13/14) : 3/7 = 17; 

102/14 : 3/7 = 17; 

102/14 * 7/3 = 17; 

(102 * 7)/(14 * 3) = 17; 

714/42 = 17; 

17 = 17. Решение верно. 

3) 3 1/16 : (х - 5/16) =7/8; 

х - 5/16 = 49/16 : 7/8; 

х - 5/16 = 49/16 * 8/7; 

х - 5/16 = (49 * 8)/(16 * 7); 

х - 5/16 = 392/112; 

х = 392/112 - 5/16; 

х = 56/16 - 5/16; 

х = 51/16. 

Проверка: 

3 1/16 : (51/16 + 5/16) =7/8;

49/16 : 56/16 = 7/8; 

49/16 * 16/56 = 7/8; 

49/56 = 7/8; 

7/8 = 7/8. Решение верно.