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

1/3+6/5−1/5+2/3=2

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

1212/1515 = 1212 :1515 

= 12 x 101 : 15 x 101 

= 12/15

dinh hoang vu

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

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

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

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

 48,25 + 12,72 + 51,75 + 87,28
  = (48,25 + 51,75) + (12,72 + 87,28)
  = 100 + 100
  = 200

 a) 48,25+12,72+51,75+87,28

= (48,25+51,75) + (12,72+ 87,28)

=         100         +         100

=                       200

200

( 742+258) + 316=1000 + 356=1356

742+316+258 = 1316

1 + 8 + 29 + 32 

= ( 1 + 29 ) + ( 8 + 32)

=       30      +      40

=              70 

mk nhóa

\(1+8+29+32\)

\(=\left(1+29\right)+\left(8+32\right)\)

\(=30+40\)

\(=70\)