4.8×7.8+78×0.52= 3.9-4.1+6.1-5.9=
1.4.8x7.8+10x7.8x0.52=7.8x(4.8+5.2)=78
2.3.9+6.1-(4.1+5.9)=0
7.8*[4.8+5.2]=78
3.9-5.9+6.1-4.1=0