(125+875)+156

=    1000 +156 =1156

(789+211)+987

=1000 +987=1987

125 + 156 + 875

= ( 125 + 875) + 156

= 1000 + 156 = 1165

789 + 987 + 211

= ( 789 + 211 ) + 987

= 1000 + 987 = 1987

=[ 125 + 875 ] + 156 

=1000 + 156 = 1156

=[ 789 + 211 ] + 987

=1000 + 987=1987

\(\dfrac{1}{3}+\dfrac{6}{5}-\dfrac{1}{5}+\dfrac{2}{3}=2\)

1/3+6/5−1/5+2/3=2

120 ****

2 x 3 x 4 x 5 

= 6 x 20 

= 120 

=[ 2 x 5 ] x [ 3 x 4 ]

= 10 x 12

= 120

1212/1515 = 1212 :1515 

= 12 x 101 : 15 x 101 

= 12/15

dinh hoang vu

\(\frac{1212}{1515}=\frac{1212\div101}{1515\div101}\)

\(=\frac{12}{15}=\frac{4}{5}\)

\(\frac{1212}{1515}=\frac{2^2.3.101}{3.5.101}=\frac{2^2}{5}=\frac{4}{5}\)

50056456+(56442424455x2)=50056456+112884848910

                                         =112934905366

2,5 x 12 ,5 x 8 x 0,4=(2,5 x 0,4 ) x(12,5 x8)

                            =1x100=100

=2,5 x 12,5 x 8 x 0,4

=(2,5 x 0,4) x (12,5 x 8)

=1 x 100

=100

Tính bằng cách thuận tiện nhất: 2,5x12,5x8x0,4=100

k mik nha

  25x20x125x8-8x20x5x125

=(25x8)x(20x125)-(20x5)x(8x125)

=200x2500-100x1000

=500000-100000=400000

mk tính giống bạn kia

giai giup minh nha

476x72+476x28

=476x(72+28)

=476x100

=47 600

476x72+476x28

=476x(72+28)

=476x100

=47 600

54x342-44x342

=342x(54-44)

=342x10

=3 420

54x342-44x342

=342x(54-44)

=342x10

=3 420

54x342-44x342

=342x(54-44)

=342x10

=3 420