(1)85×0.75+15×75%, =85×0.75+15×0.75, =(85+15)×0.75, =100×0.75, =75; (2)( 5 12 + 1 19 )×12+ 7 19 , = 5 12 ×12+ 1 19 ×12+ 7 19 , =5+( 12 19 + 7 19 ), =5+1, =6; (3)[1-( 1 3 + 1 4 )]×24, =[1- 7 12 ]×24, = 5 12 ×24, =10.
125+85+75+125.