SOLUTION: y varies directly with x, and y = 60 when x = 20. What is y when x = 16?

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Question 1109381: y varies directly with x, and y = 60 when x = 20. What is y when x = 16?
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Same problem, different numbers.
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y is directly proportional to x, and y = 20 when x = 6. What is y when x = 14?
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y = k*x
20 = k*6
k = 10/3
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What is y when x = 14?
y = 14*10/3 = 140/3
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You don't have to solve for k:
20/6 = y/14
Cross multiply
6y = 280
y = 140/3

Answer by ikleyn(52780) About Me  (Show Source):
You can put this solution on YOUR website!
.
Or this, shorter way


60%2F20 = y%2F16  ====>  y = %2860%2A16%29%2F20 = 3*16 = 48.