Question

tính nhanh

4 x 51x 7 + 2x 86x 7 + 12x 2x 7

Answer 1

4 x 51 x 7 + 2 x 86 x 7 + 12 x 2 x 7

= ( 4 x 7 ) x 51 + 2 x ( 43 x 2 ) x 7 + ( 6 x 2 ) x 2 x 7

= 28 x 51 + ( 2 x 2 x 7 ) x 43 + ( 2 x 2 x 7 ) x 6 

= 28 x 51 + 28 x 43 + 48 x 6

= 28 x ( 51 + 43 + 6 )

= 28 x 100

= 2800
 

Answer 2

4 x 51 x 7 + 2 x 86 x 7 + 12 x 2 x 7

= 2 x 7 x 2 x 51 + 2 x 7 x 86 + 2 x 7 x 12

= 14 x 102 + 14 x 86 + 14 x 12

= 14 x (102 + 86 + 12)

= 14 x 200

= 14 x 2 x 100

= 28 x 100

= 2800

Answer 3

4 x 51x 7 + 2x 86x 7 + 12x 2x 7

= 7x2x2x51 + 2 x 7 x86 + 2x7x12 

=   14 x 102 + 14 x 86    + 14 x 12

=    14 x ( 102 + 86 + 12)

=     14 x 200

=          2800

Answer 4

4 x 51 x 7 + 2 x 86 x 7 + 12 x 2 x 7

= 2 x 7 x 2 x 51 + 2 x 7 x 86 + 2 x 7 x 12

= 14 x 102 + 14 x 86 + 14 x 12

= 14 x (102 + 86 + 12)

= 14 x 200

= 14 x 2 x 100

= 28 x 100

= 2800

Answer 5

4 x 51 x 7 + 2 x 86 x 7 + 12 x 2 x 7

= 2 x 7 x 2 x 51 + 2 x 7 x 86 + 2 x 7 x 12

= 14 x 102 + 14 x 86 + 14 x 12

= 14 x (102 + 86 + 12)

= 14 x 200

= 14 x 2 x 100

= 28 x 100

= 2800

Answer 6

4 x 51x 7 + 2x 86x 7 + 12x 2x 7

= 2 x 7 x 2 x 51 + 2 x 7 x 86 + 2 x 7 x 12

= 14 x 102 + 14 x 86 + 14 x 12

= 14 x { 102 + 86 + 12 }

= 14 x 200

= 14 x 2 x 100

= 28 x 100

= 2 800

Answer 7

4 x 51 x 7 + 2 x 86 x 7 + 12 x 2 x 7

= 2 x 7 x 2 x 51 + 2 x 7 x 86 + 2 x 7 x 12

= 14 x 102 + 14 x 86 + 14 x 12

= 14 x (102 + 86 + 12)

= 14 x 200

= 14 x 2 x 100

= 28 x 100

= 2800