Question

tính hợp lí

21.35-3.45.7

 

Answer 1

21. 35 - 3. 45 . 7

= 21. 35 - 21. 45

= 21. ( 35 - 45 )

= 21. ( - 10 )

= - 210

Answer 2

21 . 35 - 3 . 45 . 7

= 21 . 35 - 3 . 7 . 45

= 21 . 35 - 21 . 45

= 21 . ( 35 - 45 )

= 21 . ( -10 )

= -210

Answer 3

21 . 35 - 3 . 45 . 7

= 21 . 35 - 21 . 45

= 21 . (35 - 45)

= 21 . (-10)

= -210