Question

tính nhanh

(15+21)+(25-15-35-21)

Answer 1

(15 + 21) + (25 - 15 - 35 - 21)

= 15 + 21 + 25 - 15 - 35 - 21

= (15 - 15) + (21 - 21) - (25 + 35)

= 0 + 0 - 60

= - 60

Answer 2

= ( 15 + 25 + 35 ) - 21

= 75 - 21

= 54

Answer 3

(15+21)+(25-15-35-21)

=15+21+25-15-35-21

=(15-15)+(21-21)-(25+35)

=0+0-60

=60

Answer 4

(15+21)+(25-15-35-21)

= 15+21+25-15-35-21

=(15-15)+(21-21)-(25+35)

=0+0+60

=60

Answer 5

(15 + 21) + (25 - 15 - 35 - 21)

= 15 + 21 + 25 - 15 - 35 - 21

= (15 - 15) + (21 - 21) - (25 + 35)

= 0 + 0 - 60

= - 60

Answer 6

(15+21)+(25-15-35-21)

=15+21+25-15-35-21

=(15-15)+(21-21)+(25-35)

=0+0+[25+(-35)]

=0+(-10)

=-10