Question

Tính nhanh:
                                      a). 125 x 12 + 12 x 874 + 12
                                      b). 34,64 x 46 + 34,64 x 53 + 34,64
                                      c). 456 x 45 + 456 x 10 – 456 x 55
                                      d).1475+399-475-199
                          

Answer 1

 a). 125 x 12 + 12 x 874 + 12

 = 12 x (125 + 874 + 1)

 = 12 x 1000

=12 000

Answer 2

mink chỉ bít câu a) thôi nha

12 x ( 125 + 874 ) = 12 x 999 

                             = 11988

Answer 3

a ) 125 x 12 + 12 x 874 + 12

= 12 x ( 125 + 874 + 1 )

= 12 x 1000

= 12000.

b) 34,64 x 46 + 34,64 x 53 + 34,64

=34,64 x ( 46 + 53 + 1 )

= 34,64 x 100

= 3464.

c) 456 x 45 + 456 x 10 - 456 x 55

= 456 x ( 45 + 10 - 55 )

= 456 x 0

= 0

d) 1475 + 399 - 475 - 199

= ( 1475 - 475 ) + ( 399 - 199 )

= 1000 + 200

= 1200.

Answer 4

                          

a ) 125 x 12 + 12 x 874 + 12
= 12 x ( 125 + 874 + 1 )
= 12 x 1000
= 12000.
b) 34,64 x 46 + 34,64 x 53 + 34,64
=34,64 x ( 46 + 53 + 1 )
= 34,64 x 100
= 3464.
c) 456 x 45 + 456 x 10 - 456 x 55
= 456 x ( 45 + 10 - 55 )
= 456 x 0
= 0
d) 1475 + 399 - 475 - 199
= ( 1475 - 475 ) + ( 399 - 199 )
= 1000 + 200
= 1200.