Question

tính bằng cách thuận tiện nhất

a,142 x12 + 142 x 18

b,49 x 365 - 39 x 356

c,4 x 18 x 25

Answer 1

a) 142 x 12 + 142 x 18

= 142 x ( 18 + 12 )

= 142 x 30

= 4260

b) 49 . 365 - 39 . 365

= 365 . ( 49 - 39)

= 365 . 10

= 3650

c) 4 . 18 . 25

= 18 . 4 . 25

= 18 . 100

= 1800

Answer 2

a, 142 x 12 + 142 x18=142 x (12+18)= 4260

b, 49 x 365 - 39 x356 = 356 x (49-39)= 3560

c,4 x 18 x 25 = (25 x 4) x 18=1800

Answer 3

a,142 x 12 + 142 x 18 

=142 x (12+18)

=4260

b,49 x 365 - 39 x 365

= 365 x ( 49 -39 )

=365 x 10

=3650

c,4 x 18 x 25

=(4 x 25 ) x 18

= 100 x 18

= 1800

 

Answer 4

a,142 x 12 + 142 x 18

=142 x (18 + 12 )

=142 x 30\

=4260