Đáp án:
Giải thích các bước giải:
`2/2÷3/3×4/4+5/6×3/4÷4/4-6/6+7/9`
`= 2/2×3/3 × 4/4 + 5/6 × 3/4 : 4/4- 6/6 + 7/9`
`= 1 × 1 ×1 +5/6×3/4×1 - 1 +7/9`
`= ( 1 × 1 ×1 ×1) + ( 5/6 × 3/4 ) - 1 + 7/9`
`= 1 + 5/8 - 1 + 7/9`
`= 1 + 5/8 - 1 + 7/9`
`=[1 + ( -1) ] + 5/8 + 7/9`
` = 0 + 5/8 + 7/9 =101/72`
