SOLUTION: If y varies directly as x, and y = 9 when x = 12, find the value of y when x = 7.

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Question 4063: If y varies directly as x, and y = 9 when x = 12, find the value of y when x = 7.
Answer by gsmani_iyer(178) About Me  (Show Source):
You can put this solution on YOUR website!
y varies directly as x

So y%2Fx = 9%2F12
if x = 7, then
9%2F12 = y%2F7
By cross multiplication, we get
12y = 63
y = 63%2F12 = 51%2F4 = 21%2F4
by replacing this value of y,
%2821%2F4%29%2A%281%2F7%29
= 21%2F28
= 5.25%2F7
So x = 5.25 Answer
I hope this is clear to you

gsm