If y varies directly with x and y = 3 when x = 12, then what is the value of y when x = 40?

Question

Question 1 options:

10

480

4

160

Answer 1

To find the value of y when x = 40, we can use the formula for direct variation:

y = kx

To solve for k, we can use the given information that y = 3 when x = 12:

3 = k(12)

Dividing both sides by 12, we get:

k = 3/12

Simplifying, we get:

k = 1/4

Now we can substitute this value of k into the equation to find y when x = 40:

y = (1/4)(40)

Multiplying, we get:

y = 10

Therefore, the value of y when x = 40 is 10.