Question

9+8+7+6+5+4+3+2+1=..........   tính bằng cánh nhanh nhất

 

Answer 1

(9+1)+(8+2)+(7+3)+(6+4)+5

Answer 2

9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1

= ( 9 +1 ) + ( 8 + 2 ) + ( 7 + 3 ) + ( 6 + 4 ) + 5

= 10 + 10 + 10 + 10 + 5

= 40 + 5

= 45

Answer 3

Giải:

(9+1)+(8+2)+(7+3)+(6+4)+(5+5)=

=10+10+10+10+10

=50

đáp số 50

Answer 4

9+8+7+6+5+4+3+2+1

= ( 9+1 ) + ( 8+2 ) + ( 7+3 ) + ( 6+4 ) + 5

= 10 + 10 + 10 + 10 + 5

= 40 + 5 

= 45

Answer 5

9+8+7+6+5+4+3+2+1

=(9+1)+(8+2)+(7+3)+(6+4)+5

=10+10+10+10+5

=40+5

=45

Answer 6

9+8+7+6+5+4+3+2+1

=(9+1)+(8+2)+(7+3)+(6+4)+5

=10+10+10+10+5

=20+20+5

=40+5=45

Answer 7

Minh tra loi dau do kick mn mn dang am diem

Answer 8

9+8+7+6+5+4+3+2+1=(9+1)+(8+2)+(7+3)+(6+4)+5=10+10+10+10+5=45