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