Найти значение выражения:
1)1 4/15+6 13/45-7/12;
2)10 5/28+ (6/7-3/14);
3)8 7/12-5/18+1 3/4-2 1/6

Предыдущий
вопрос Следующий
вопрос

1) 1 4/15 + 6 13/45 - 7/12 = 1 + 4/15 + 6 + 13/45 - 7/12
= 7 + 4/15 + 13/45 - 7/12
= 7 + (43)/(153) + 13/(315) - 7/(125)
= 7 + 12/45 + 13/45 - 7/60
= 7 + 25/45 - 7/60
= 7 + (254)/(454) - 7/60
= 7 + 100/180 - 7/60
= 7 + 100/180 - 21/180
= 7 + 79/180
= 7 79/180

2) 10 5/28 + (6/7 - 3/14) = 10 + 5/28 + (6/7 - 3/14)
= 10 + 5/28 + (12/14 - 3/14)
= 10 + 5/28 + 9/14
= 10 + 5/28 + (92)/(142)
= 10 + 5/28 + 18/28
= 10 + 23/28
= 10 23/28

3) 8 7/12 - 5/18 + 1 3/4 - 2 1/6 = 8 + 7/12 - 5/18 + 1 + 3/4 - 2 - 1/6
= 8 + 7/12 - 5/18 + 1 + (33)/(43) - 2 - 1/6
= 8 + 7/12 - 5/18 + 1 + 9/12 - 2 - 1/6
= 8 + 21/36 - 10/36 + 12/12 - 2 - 1/6
= 8 + (21-10)/36 + 1 - 2 - 1/6
= 8 + 11/36 - 1 - 2 - 1/6
= 8 + 11/36 - 36/36 - 72/36 - 6/36
= 8 - 61/36
= 7 25/36