Question

Tính nhanh:

a.16x50x(-25)x(-250)

b.-54x76+12x(-76)

c.32x(-64)-64x68

d.19x42.(-19)+38x5

Answer 1

a,16 X 50X-25X(-250)

=(16 X-25)X50X(-250)

=-400X50X-250

=-20000X-250

=5000000

b,-54X76+12X(-76)

=76X(-54-12)

=76X(-66)

=-5016

c,32X(-64)-64X68

=-64X(32+68)

=-64X100

=-6400

d,19X42.(-19)+38X5

=19X(42-1)+19X2X5

=19X41+19X10

=19X(41+10)

=19X51=969

Answer 2

a) 16.50.(-25).(-250)

=[16.(-25)].50.(-250)

=-400.50.(-250) 

=-20000.(-250) 

=5000000

b,-54.76+12.(-76)

=76.(-54-12)

=76.(-66)

=-5016

c,32.(-64)-64.68

=-64.(32+68)

=-64.100

=-6400

d,19.42.(-19)+38.5

=19.(42-1)+19.2.5

=19.(42-1)+19.(2.5)

=19.41+19.10

=19.(41+10)

=19.51

=969 

Answer 3

a. 16\(\times\)50\(\times\)(-25)\(\times\)(-250)

=(4\(\times\)4)\(\times\)50\(\times\)25\(\times\)250

=4\(\times\)4\(\times\)50\(\times\)25\(\times\)250

=(4\(\times\)25)\(\times\)(4\(\times\)250)\(\times\)50

=100\(\times\)1000\(\times\)50

=5000000

b. -54\(\times\)76+12\(\times\)(-76)

=54\(\times\)(-76)+12\(\times\)(-76)

=(-76)\(\times\)(54+12)

=(-76)\(\times\)66

= -5016

c. 32\(\times\)(-64)-64\(\times\)68

=(-32)\(\times\)64-64\(\times\)68

=64\(\times\)(-32-68)

=64\(\times\)(-100)

= -6400

d. 19\(\times\)42\(\times\)(-19)+38\(\times\)5

=19\(\times\)(2\(\times\)21)\(\times\)(-19)+38\(\times\)5

=19\(\times\)2\(\times\)21\(\times\)(-19)+38\(\times\)5

=38\(\times\)21\(\times\)(-19)+38\(\times\)5

=38\(\times\)(-399)+38\(\times\)5

=38​\(\times\)​(-399+5)

=38\(\times\)(-394)

= -14972