The value of y is directly proportional to the value of x. if y=65 when x=5, what is the value of y when x=12?

Y=65
X=5
X=12
Y=?

65—->5
?——>12

Cross multiply

Y= (65x12) / 5
Y= 780 / 5
Y= 156

To check add the Y value in and remove an X value

65——> ?
156 ——> 12

Cross multiply

X= (12x65) / 156
X= 780 / 156
X= 5

You got the right answer. Hope this helped.

If you make it a little more clear i can answer it

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