Question

1 + 2 + 3 + 4 + 5 + 6 + 7 =...

Answer 1

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

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

= 8 + 8 + 8 + 4

= 8 x 3 + 4

= 24 + 4 = 28

Answer 2

1+2+3+4+5+6+7 = 28

NHỚ ****!!!~~~

 

 

 

 

Answer 3

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

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

= 8 + 8 + 8 + 4

= 8 x 3 + 4

= 24 + 4 = 28