Объяснение:
3 1/3*4 1/5+3 1/3*2 4/5=3 1/3*(4 1/5+2 4/5)=3 1/3*7
4,2*2/3+2,8*2/3=2/3*(4,2+2,8)=2/3*7
3 1/3*7+2/3*7=7*(3 1/3+2/3)=7*4=28
Объяснение:
3 1/3*4 1/5+3 1/3*2 4/5=3 1/3*(4 1/5+2 4/5)=3 1/3*7
4,2*2/3+2,8*2/3=2/3*(4,2+2,8)=2/3*7
3 1/3*7+2/3*7=7*(3 1/3+2/3)=7*4=28