0,75×1/9+1/8-0,8×3/8=

(0,75 x 1/9) + 1/8 - (0,8 x 3/8)
= (75/100 x 1/9) + 1/8 - (8/10 x 3/8)
= 75/900 + 1/8 - 3/10
= 0,083 + 0,125 - 0,3
= 0,208 - 0,3
= - 0,092

0.75x1/9 + 1/8 - 0.8 x 3/8
75/100 x 11,11/100 + 12,5/100 - 80/100 x 37.5/100
833.25/100 + 12,5/100 - 3000/100
0.83325 + 0.12500 - 30
0.84575 - 30 = -2154