1) 2 1/2 * 0,24=5/2*0,24=2,5*0,24=0,6
2) 0,6-15/19= 6/10-15/19 = 3/5-15/19 =( 3 × 19-15 × 5 )/95 = 57/95 - 75/95 = -18/95
3)5,45+1 4/45=5,45+49/45=5 45/100 + 49/45 = 109/20 + 49/45 = (109 × 9 + 49 × 4)/180 = 981/180 + 196/180 = 1177/180 = 6 97/180
4) 6 97/180 - 6 1/8 = 1177/180 - 49/8 =(1177 × 2 - 49 × 45)/360 = 2354/360 - 2205/360 = 149/360
5)28,14÷3,5=8,04
6)-18/95*149/360=-149/1900
7)8,04-(-149/1900)=8 4/100 - (- 149/1900) 8 4/100 + 149/1900 = 201/25 + 149/1900 =(201 × 76 + 149 × 1)/1900 = (15276 + 149)/1900 = 15425/1900 = 617/76 = 8 9/76ответ 8 9/76