Question

Tính nhanh :  39 - 24 + 1 - 26 + 50

Answer 1

= (39+1) -(24+26) +50

=40- 50 +50 = 40 +0 = 40

Answer 2

   39 - 24 + 1 - 26 + 50 

= ( 39 + 1 ) + ( 50 - 24 - 26 )

= 40 + (50 - 50 )

= 40 + 0 

= 40 

Answer 3

39 - 24 + 1 - 26 + 50 = (39 + 1) + (50 - (24 + 26)) = 40 + 50 - 50 = 40