Đáp án + Giải thích các bước giải:
Ta có :
`\frac{4}{5}xx0,5+\frac{12}{5}xx0,3+\frac{8}{10}xx0,2`
`=\frac{4}{5}xx5xx0,1+\frac{12}{5}xx3xx0,1+\frac{4}{5}xx2xx0,1`
`=\frac{20}{5}xx0,1+\frac{36}{5}xx0,1+\frac{8}{5}xx0,1`
`=4xx0,1+\frac{36}{5}xx0,1+\frac{8}{5}xx0,1`
`=0,1xx(4+\frac{36}{5}+\frac{8}{5})`
`=0,1xx\frac{64}{5}`
`=\frac{32}{25}`
Vậy `\frac{4}{5}xx0,5+\frac{12}{5}xx0,3+\frac{8}{10}xx0,2=\frac{32}{25}`