Đáp án:
Giải thích các bước giải:
`a, (1/3 + 2/5) × 3/4`
`C1: (1/3 + 2/5) × 3/4`
`= 11/15 × 3/4`
`= 11/20`
`C2: (1/3 + 2/5) × 3/4`
`= 1/3 × 3/4 + 2/5 × 3/4`
`= 1/4 + 3/10`
`= 11/20`
`b, (7/9 + 2/3)÷ 5/6`
`C1: (7/9 + 2/3)÷ 5/6`
`= 13/9 ÷ 5/6`
`= 26/15`
`C2: (7/9 + 2/3)÷ 5/6`
`= 7/9 ÷ 5/6 + 2/3÷ 5/6`
`= 14/15 + 4/5`
`= 26/15`