Question

Tính nhanh :

a, 29+132+237+868+763

b, 35 * 34 + 35 * 38 + 65 * 75 +45 

c, 3 * 25 *8 +4*37*6 +2*38*12

Answer 1

a)      29 + 132 + 237 + 868 + 763

    =  ( 132 + 868 ) + ( 237 + 763 ) + 29

    = 1000 + 1000 + 29

    =  1000 x 2 + 29

    =  2000 + 29

    =  2029

b)    35 x 34 + 35 x 38 + 65 x 75 + 45

    =  35 x ( 34 + 38 ) + 65 x 75 + 45

    =  35 x 72 + 65 x 75 + 45

    =  2520 + 4875 + 45

    =  2520 + 4920

    =  7440

c)     3 x 25 x 8 + 4 x 37 x 6 + 2 x 38 x 12

    =  ( 3 x 8 ) x 25 + ( 4 x 6 ) x 37 + ( 2 x 12 ) x 38

    =   24 x 25 + 24 x 37 + 24 x 38

    =   24 x ( 25 + 37 + 38 )

    =   24 x 100

    =   2400

Answer 2

a)29+132+237+868+763

=(132+868)+(237+763)+29

=     1000   +   1000    +29

=      2029

Answer 3

a,29+132+237+868+763

=29+(132+868)+(237+763)

=29+1000+1000

=2029

Answer 4

a) \(29+132+237+868+763\)

\(=\left(132+868\right)+\left(237+763\right)+29\)

\(=1000+1000+29\)

\(=2029\)

b) \(35.34+35.38+65.75+45\)

\(=35.\left(34+38\right)+4875+45\)

\(=35.72+\left(4875+45\right)\)

\(=2520+4920\)

\(=7440\)

Answer 5

c)3*25*8+4*37*6+2*38*12

=(3*8)*25+(4*6)*37+(2*12)*38

=24*25+24*37+24*38

=24*(25+37+38)

=2400

Answer 6

a,

29+132+237+868+763=

=(132+868)+(237+763)+29

=1000+1000+29

=2029