y varies directly with x, and y = 2 when x = 5.
What is the value of x when y = 15?
A. x = 25
B. x = 10
C. x = 6
D. x = 37.5
To solve this problem, we can use the concept of direct variation. In a direct variation, the relationship between two variables (in this case, x and y) can be represented by the equation y = kx, where k is called the constant of variation.
Given that y varies directly with x and y = 2 when x = 5, we can substitute these values into the equation to find the value of k:
2 = k * 5
To find the value of k, divide both sides of the equation by 5:
k = 2/5
Now that we know the value of k, we can use it to find the value of x when y = 15. We plug in the values of y and k into the direct variation equation and solve for x:
15 = (2/5) * x
To find x, we multiply both sides of the equation by 5/2:
x = (15 * 5)/2
x = 37.5
Therefore, the value of x when y = 15 is x = 37.5. So, the correct answer is D.