Thực hiện phép tính A/ 10/21 × -14/3 + 5/9 B/ 7/8 × 7/13 + 7/8 × 9/13 – 7/8 × 3/13

0 bình luận về “Thực hiện phép tính A/ 10/21 × -14/3 + 5/9 B/ 7/8 × 7/13 + 7/8 × 9/13 – 7/8 × 3/13”

1. `a)“10/21*(-14)/3+5/9`

   `=(-140)/63+5/9`

   `=(-20)/9+5/9`

   `=(-15)/9`

   `b)“7/8 * 7/13+7/8 * 9/13-7/8 * 3/13`

   `=7/8*(7/13+9/13-3/13)`

   `=7/8*((7+9-3)/13)`

   `=7/8*13/13`

   `=7/8 . 1`

   `=7/8`

    

   Bình luận

2. `#Kenshiro`

   `a ) 10/21 xx` `\frac{-14}{3}` `+ 5/9`

   `=` `\frac{-140}{63}` `+ 5/9`

   `=` `\frac{-140}{63}` `+ 35/63 =` `\frac{-105}{63}` `=` `\frac{-15}{9}`

   `b ) 7/8 xx 7/13 + 7/8 xx 9/13 – 7/8 xx 3/13`

   `= 7/8 . (7/13 + 9/13 – 3/13 )`

   `= 7/8. 13/13`

   `= 91/104 = 7/8`

    

   Bình luận