Решите пример:

3 23/15 + 7,45 - 1 11/25 - 4 13/75

3 1/13 x (3/5 + 7/8) - 1 2/26

3 23/15 + 7,45 - 1 11/25 - 4 13/75=

{3 23/15 + 7 9/20} - {1 11/25 + 4 13/75}=

{ 3 (23•4) / (15•4) + 7 (9•3) / (20•3) } - { 1 (11•3) / (25•3) + 4 13/75}=

{ 3 92/60 + 7 27/60} - { 1 33/75 + 4 13/75} =

10 119/60 - 5 46/75=

11 59/60 - 5 46/75=

11 (59•5) / (60•5) - 5 (46•4) / (75•4) =

11 295/300 - 5 184/300=

6 111/300 = 6 (111:3) / (300:3) =

6 37/100 = 6,37

{7,45 = 7 45/100 = (7•100+45) / 100 = 745/100 = (745:5) / (100:5) = 149/20 = 7 9/20}

3 1/13 x (3/5 + 7/8) - 1 2/26=

(3•13+1) / 13• 3/5 + (3•13+1) / 13• 7/8 - 1 2/26=

40/13• 3/5 + 40/13• 7/8 - 1 (2:2) / (26:2) =

8/13• 3/1 + 5/13• 7/1 - 1 1/13=

{сократили 40 и 5 на 5; 40 и 8 на 8}

= 24/13 + 35/13 - (13•1+1) / 13=

59/13 - 14/13 = 45/13 = 3 6/13