Lay (59/18 + 46/9) + (75/14 + 15/7) + (5/2 + 47/18)

De et a

= 17/7 + 4/7 - 2/5 + 3/5

= 21/7 - 5/5

= 3 - 1

= 2

=3x2/3 x 2/4

=2x1/2

=1

=1

k cko mik nha mái pn

\(a,\dfrac{5}{9}\times\dfrac{5}{2}+\dfrac{4}{9}\times\dfrac{5}{2}=\dfrac{5}{2}\times\left(\dfrac{5}{9}+\dfrac{4}{9}\right)=\dfrac{5}{2}\times1=\dfrac{5}{2}\)

\(12\times\dfrac{3}{4}-\dfrac{3}{4}\times\dfrac{12}{7}=\dfrac{3}{4}\times\left(12-\dfrac{12}{7}\right)=\dfrac{3}{4}\times\dfrac{72}{7}=\dfrac{54}{7}\)

  -1/2+3/5+(-1/2)+1/127+(-7/18)+4/35+2/7

=(-1/2+(-1/2))+(3/5+4/35)+(1/127+(-7/18))+2/7

=-1/1+5/7+(-871/2286)+2/7

=(-1/1+5/7+2/7)+(-871/2286)

=0+(-871/2286)

=-871/2286

2x25x50xx8=(25x8)x(50x2)=200x100=20000

12x11+21x11+11x33=11x(12+21+33)=11x66=726

2*25*50*8

=(2*50)*(25*8)

=100*200=20000

12*11+21*11+11*33

=11*(12+21+33)

=11*66=676

2 x 25 x 50 x 8  = (8 x 25) x (50 x 2) = 200 x 100 = 20000

b) 12 x 11 + 21 x 11 + 11 x 13 = 11 x (12 + 21 + 33) 

= 11 x 66 = 726

a) (3/4 + 3/12) + 2/5=7/5
b) (47/15 - 4/30) + (40/17 - 6/17)= 3 - 2 =1

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