Question

cine ma poate ajuta îi dau coroana, si e urgeeent va rog​

Answer 1

Răspuns:

Explicație pas cu pas:

Answer 2

Răspuns:

Explicație pas cu pas:

6)  

a) ( 2/3) · x = 4/15

    x = ( 4/15) : ( 2/3) = ( 4/15) × (3/2)

    x = 2/5

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b)

x : ( 6/7) = 14/9

x = ( 14/9) × ( 6/7)

x = (14/7) ×(6/9)

x = (2×2)/3

x = 4/3

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c)

(24/25) : x = 18/5

x = (24/25) : ( 18/5) = ( 24/25 ) × (5/18) = (5/25) × (24/18)

x = (1/5) × (4/3)

x = 4/15

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7)

a) (1/2)× x + 1/4 = 1/3

   (1/2)× x = 1/3 - 1/4 = ( 4 - 3)/12 = 1/12

     x = ( 1/12) : ( 1/2) = ( 1/12) × 2

    x = 1/6

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b)  

x : ( 3/4) - 1/3 = 1/9

x : (3/4) = 1/9 + 1/3 = 1/9 + 3/9 = 4/9

x = (4/9) × (3/4)

x = 1/3

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c)

(5/8) : x - 1/4 = 1/2

(5/8) : x = 1/2 + 1/4 = 2/4 + 1/4 = 3/4

x = (5/8) : (3/4) = ( 5/8) × (4/3)

x = 5/6

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8)

a)   a = 4/9;  b = 1/3   si  c = 1/5

a : b : c = (4/9) : (1/3) : (1/5) = (4/9) x 3 x 5 = 20/3

a : (b x c ) = 4/9 : ( 1/3  x  1/5 ) = (4/9) : 1/15 = (4/9) x 15 = 20/3

=>   a : b : c = a : ( b x c )

          20/3 =  20/3  Adevarat

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b)   a = 2 intregi si 3/7;   b = 17/15   si   c = 2 intregi si 1/7

=> introduc intregii in fractie

a = (2 x 7 + 3)/7 =>  a = 17/7

c = ( 2 x 7 +1)/7 =>  c = 15/7

a : b : c = (17/7) : (17/15) : (15/7 ) = (17/7) x (15/17) x (7/15 ) = 1

a : ( b x c ) = ( 17/7 ) : ( 17/15  x 15/7 ) = (17/7) : 17/7= (17/7) x (7/17) = 1

=> a : b : c = a : ( b x c ) = 1   Adevarat)

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9).

a)  a/b =8/15  si  c = 400

(8/15) din X = 400 =>    X = 15 x 400 : 8 =>   X = 750

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b)  a/b = 4/9  si  c = 120

(4/9) din X = 120 =>   X = (120 x 9 ) : 4 =>   X = 270

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c)  a/b = 1/6   si  c = 150

(1/6 ) din X = 150 =>   X = 6 x 150   =>   X = 900

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10)

a)  c = 2/5  si  X = 2 intregi si 1/5 = ( 2 x 5 + 1 )/5 =>  X = 11/5

( a/b ) x  11/5 = 2/5

a/b = (2/5) : 11/5 = (2/5) x (5/11) =>   a/b = 2/11

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b)  c = 2/5  si  X = 18/5

(a/b) x 18/5 = 2/5

a/b = (2/5) : 18/5 = (2/5) x (5/18)  => a/b = 1/9