Question

If x and y are in direct proportion and y is 45 when x is 15, find y when x is 4

Answer 1

Explanation:

Since x and y are in direct proportion, we know that:

y = kx

where k is the constant of proportionality. We can find k by using the given information:

45 = k * 15

Dividing both sides by 15 gives:

k = 3

Now that we know the value of k, we can use it to find y when x is 4:

y = k * x = 3 * 4 = 12

So, when x is 4, y is 12.