a: =17/25(13/19+6/19)=17/25

b: \(=\dfrac{47}{19}\cdot\dfrac{32}{15}-\dfrac{47}{19}\cdot\dfrac{17}{15}=\dfrac{47}{19}\)

`17/25xx(13/19+6/19)`

`17/25xx1`

`17/25`

`a)17/25xx13/19+17/25xx6/19`

`=17/25xx(13/19+6/19)`

`=17/25xx19/19=17/25`

`b)47/19:15/32-47/19:15/17`

`=47/19xx32/15-47/19xx17/15`

`=47/19xx(32/15-17/15)`

`=47/19xx15/15=47/19`

A.\(=\frac{17}{25}\times\left(\frac{13}{19}+\frac{6}{19}\right)\)

\(=\frac{17}{25}\times1\)

\(=\frac{17}{25}\)

B\(=\frac{47}{19}:\left(\frac{15}{32}-\frac{15}{17}\right)\)

\(=\frac{47}{19}:1\)

\(=\frac{47}{19}\)

\(\dfrac{47}{19}:\dfrac{15}{32}-\dfrac{47}{19}:\dfrac{15}{17}\\ =\dfrac{47}{19}\times\dfrac{32}{15}-\dfrac{47}{19}\times\dfrac{17}{15}\\ =\dfrac{47}{19}\times\left(\dfrac{32}{15}-\dfrac{17}{35}\right)\\ =\dfrac{47}{19}\times1\\ =\dfrac{47}{19}\)

`@An`

a, \(\frac{2}{5}\)x ( \(\frac{3}{7}\)+\(\frac{4}{7}\))

= \(\frac{2}{5}\)x  \(\frac{7}{7}\)

= \(\frac{2}{5}\)x 1

= \(\frac{2}{5}\)

b, \(\frac{47}{19}\) :\(\frac{15}{32}\) - \(\frac{47}{19}\) :\(\frac{15}{17}\)
= \(\frac{47}{19}\) × \(\frac{32}{15}\) - \(\frac{47}{19}\) × \(\frac{17}{15}\)
= \(\frac{47}{19}\) × (\(\frac{32}{15}\)-\(\frac{17}{15}\))
= \(\frac{47}{19}\) × 1
= \(\frac{47}{19}\)

a ) =

b) <

c) > 

d >

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d,=

45-58+(-45)+(+58)-3=45-58-45+58-3=(45-45)+(58-58)-3=-3

(-57)-(-12)+3-(-57)=-57+12+3+57=(-57+57)+12+3=15

-(-24)-(-30)+(-24)-30+8=24+30-24-30+8=(24-24)+(30-30)+8=8

-(-12)+(+19)-(+12)+8-19=12+19-12+8-19=(12-12)+(19-19)+8=8

47-(-53)+(-47)-(+53)=47+53-47-53=(47-47)+(53-53)=0

-(+28)+32-(-28)+(-34)=-28+32+28-34=(-28+28)-(34-32)=-2

15-(+72)+(-15)+(+72)=15-72-15+72=(15-15)+(72-72)=0

20-(+46)+(-25)-(-46)=20-46-25+46=(20-25)+(46-46)=-5

28-(-32)+(-28)-32+5=28+32-28-32+5=(28-28)+(32-32)+5=5

-75+(-49)+(+75)+49-12=-75-49+75+49-12=(-75+75)+(49-49)-12=-12

\(...=45-58-45+58-3=-3\)

\(...=-57+12+3+57=15\)

\(...=24+30-24-30+8=8\)

\(...=12+19-12+8-19=8\)

\(...=47+53-47-53=0\)

\(...=-28+32+28-34=-2\)

\(...=15-72-15+72=0\)

\(...=20-46-25+46=-5\)

\(=...28+32-28-32+5=5\)

\(...=-75-49+75+49-12=-12\)

a: =25x100-150=2500-150=2350

c: \(=520:\left\{515\cdot25\right\}\)

=104/2575

(47 - 52). 3 + 27

= -5. 3 + 27

= -15 + 27

= 12

-4(39 - 19) + 30(-5 - 15)

= -4. 20 + 30. (-20)

= -80 - 600

= -680

36. (-9) + 9. (-64)

= -9(36 + 64)

= -9. 100

= -900

\(\dfrac{15}{17}+\dfrac{32}{17}=\dfrac{15+32}{17}=\dfrac{47}{17}\)

47 - 52). 3 + 27

= -5. 3 + 27

= -15 + 27

= 12

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