Question

If x and y are in direct proportion and y is 45 when x is 9 find y when x is 15

Answer 1

If x and y are in direct proportion, it means that they can be related by a constant ratio. In mathematical terms, this relationship can be expressed as:

(x₁ / y₁) = (x₂ / y₂)

In this case, you are given that when x is 9, y is 45. So, let's use this information to set up a proportion:

(9 / 45) = (15 / y)

Now, cross-multiply and solve for y:

9 * y = 45 * 15

9y = 675

y = 675 / 9

y = 75

So, when x is 15, y is 75.