Answer:
Option a. Y=3x
Step-by-step explanation:
Let us use cross multiplication method.
Let the cost of 1 magazine be x.
No. of copies Cost
1)50 $150
2)1 x
50x=150 x 1 equation(1)
x=150/50
x=$3
Now see equation (1),
150=50x
150=50 x 3
Here let us represent the cost as y and no. of copies as x.
Y=3x
Therefore, a. Y=3x is the right answer.
Thank you!