Question

найдите значение выражения
6 5/9 (n-9)+2 2/9 (18-n) при n= 0,3

Answer 1

1) 6 ( 5/9 ) = 59/9 ; 2) ( 59/9 ) * ( n - 9 ) = ( 59/9) n - 59 ; 3) 2 ( 2/9 ) = 20/9 ; 4) ( 20/9 ) * ( 18 - n ) = 40 - ( 20/9) n ; 5) ( 59/9 ) n - 59 + 40 - ( 20/9 ) n = ( 79/9 ) n - 19 ; 6) при n = 0,3 = 3/10 ; ( 79/9 ) * ( 3/10 ) - 19 = ( 237/90 ) - 19 = 2 ( 57/90 ) - 19 = 2 ( 19/30 ) - 18 ( 30/30 ) = - 16 ( 11/30 )