a) (0,2+0,08):0,001=0,28:0,001=28/100×1000=280
b) {1+[5,8-1,1]}:0,8={1+4,7}:0,8=5,7:0,8=57/10:8/10=57/10×10/8=7
c) 7,3-100×0,04+1,2=7,3-4+1,2=3,3+1,2=4,5
d) [6/10:42/10+324/99×275/100]:{[5:1/6-10:1/2]:1/2+1/2}=[6/10×10/42+22275/2475]:{[5×6-10×2]:1/2+1/2}=[1/7+9]:{[30-20]:1/2+1/2} amplificãm pe 9 cu 7
64/7:{10×2+1/2}=64/7:{20+1/2} amplificãm pe 20 cu 2
64/7:41/2=64/7×2/41=128/287
