8.Tính bằng 2 cách A: 2/3 : 5/4 : 7/6 B: 2/3 : 4/3 : 5/4 C:2: 2/3 : 3/4

0 bình luận về “8.Tính bằng 2 cách A: 2/3 : 5/4 : 7/6 B: 2/3 : 4/3 : 5/4 C:2: 2/3 : 3/4”

1. Đáp án:

    `a)` `16/35`

   `b)` `2/5`

   `c)` `4`

   Giải thích các bước giải:

   `a)` `2/3÷5/4÷7/6 `     

   `=2/3×4/5÷7/6`

   `=8/15×6/7

   `=16/35`

   `2/3÷5/4÷7/6 `

   `=(2/3×6/7)×4/5`

   `=4/7×4/5`

   `=16/35`

   $\\$

   `b)` `2/3÷4/3÷5/4`

   `=2/3×3/4÷5/4`

   `=1/2×4/5`

   `=2/5`

   `2/3÷4/3÷5/4`

   `=(2/3×4/5)×3/4`

   `=8/15×3/4`

   `=2/5`

   $\\$

   `c)` `2÷2/3÷3/4`

   `=2×3/2÷3/4`

   `=3×4/3`

   `=4`

   `2÷2/3÷3/4`

   `=(2×4/3)×3/2`

   `=8/3×3/2`

   `=4`

   Bình luận

2. Đáp án:

    

   Giải thích các bước giải:

    ` 2/3 : 5/4 : 7/6 `

   ` = 2/3 × 4/5 × 6/7 `

   `= 8/15 × 6/7 `

   `= 16/35 `

   ` 2/3 : 5/4 : 7/6 `

   `= ( 2/3 : 7/6 ) × 4/5 `

   `= ( 2/3 × 6/7 ) × 4/5 `

   `= 4/7 × 4/5 `

   `= 16/35 `

   `b) 2/3 : 4/3 : 5/4 `

   `= 2/3 × 3/4  × 4/5 `

   `= 1/2 × 4/5 `

   `= 2/5 `

   ` 2/3 : 4/3 : 5/4 `

   `= ( 2/3 × 4/5 ) × 3/4 `

   `= 8/15 × 3/4 `

   `=2/5 `

   `c) 2 : 2/3 : 3/4 `

   `= 2 × 3/2 × 4/3 `

   `= 3 × 4/3 `

   `= 4 `

   ` 2 : 2/3 : 3/4 `

   `= ( 2 × 3/4 ) × 3/2 `

   `= 8/3 × 3/2 `

   `=4 `

   Bình luận