<PRE><B>Question 205658</B>
(3)y= kx,,,,,,,that  is  y varies  directly with  x
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8 = k * (16),,,,,,,when  y=8, x=16,,,,,,find  k
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k=8/16 =1/2
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Variation  is,,,,y = 1/2 * x
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when  x= 46,,,,,,,,y = (1/2) * 46 = 23
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check,,,8/16  =  23/46,,,,,ok
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(5)  y=kx,,y  varies  directly  with  x
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2=k*4,,,,when  y=2,,,x=4,,,,find  k
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k=1/2
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Variation  is ,,,,y= 1/2 *x
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y= (1/2)*45 =22.5
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check 22.5 /45 = 2/4,,,,ok
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(7) y= k/x,,,,,,,y  varies  in directly  with  x
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10=k/25,  y=10  when  x=25,,,find  k
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250 = k
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Variation  is,,,,y = 250/x
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y= 250/35 = 7.14,,,,,find  y  if  x=35
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check,,,y=k/x,,,xy =k = 10 * 25 = 7.14 * 35 = 250,,,ok
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