Question

1+2+3+4+5+6+7+8+9+10=.......

Answer 1

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

= ( 1 + 10) x 10 : 2

= 11 x 5

= 55

Answer 2

1+2+3+4+5+6+7+8+9+10=(10+1)x10:2=55

Answer 3

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

= ( 1 + 10 ) x 10 : 2

=     11       x      5

=              55

Answer 4

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

= ( 1 + 10) x 10 : 2

= 11 x 5

= 55 

Answer 5

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

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

= 10 + 10 + 10 + 10 + 15

= 10 x 4 + 15

= 40 + 15

= 55

Answer 6

(1+10)*5=11*5=55

Answer 7

Theo bài ra , ta có : 

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

= ( 1 + 10) x 10 : 2

= 11 x 5

= 55 

Answer 8

Theo bài ra , ta có : 

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

= ( 1 + 10) x 10 : 2

= 11 x 5

= 55 

Answer 9

Theo bài ra , ta có : 

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10

= ( 1 + 10) x 10 : 2

= 11 x 5

= 55