Question

Tính nhanh

321 + { -15 + [ 30 + ( - 321)] }

( 2016 + 432 ) + ( 168 + ( - 2016)

 

Answer 1

321 + { -15 + [ 30 + (-321) ] }

= 321 + { -15 + [ 30 - 321 ] }

= 321 + { -15 + 30 - 321 }

= 321 - 15 + 30 - 321

= (321 - 321) - (15 - 30)

= 0 - (-15)

= 15

(2016 + 432) + [168 + (-2016) ]

= 2016 + 432 + [ 168 - 2016 ]

= 2016 + 432 + 168 - 2016

= (2016 - 2016) + (432 + 168)

= 0 + 600

= 600

Answer 2

minh khong biet dau minh chi moi lop 5 thoi 

chuc ban nam moi vui ve 

thank you very much