Ответы и объяснения

2012-12-11T15:59:51+04:00

(9- 2 2/3* 2 1/7)* 21/46= (9- 8/3 * 15/7)* 21/46= (9 - 120/21)* 21/46 = 

(9*21)/46 - (120*21)/(21*46)= 189/46 - 120/46 = 69/46 = 1 23/46= 1 1/2