Question

Tính nhanh : 

a ) 43 x 27 + 93 x 43 + 57 x 61 x 59 x 57

b ) 64 x  6 + 81 x 4 + 17 x 6

Answer 1

     43 x 27 + 93 x 43 + 57 x 61 + 59 x 57 

  = 43 x ( 27 + 93 ) + 57 x ( 61 + 59 )

  =  43 x 120 +  57 x 120

  = 120 x ( 43 + 57 )

   = 120 x 100

  = 1200

b) 64 x 6 + 81 x 4 + 17 x 6 

 = 6 x ( 64 + 17 ) + 81 x 4 

 =  6 x 81 + 81 x 4 

 = 81 x ( 6 + 4 ) 

 = 81 x 10 

 = 810

Answer 2

A) =43 x (27+93)+57*(61+59)

=43*120+57*120

=120*(43+57)

=120*100

=12000