Question 453910
The variables x and y vary directly.
y = kx
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Solve for "k" using "When x is 5, y is 15". 
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15 = k*5
k = 3
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Equation:
y = 3x
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Solve: If x is 25, what is y? 
y = 3*25
y = 75
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Cheers,
Stan H.
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a. 1/3
b. 3
c. 25/3
c. 75