the cost C varies directly as the number in of penals is written as?

C = kn

If the cost C varies directly as the number N of penals, it means that the cost is directly proportional to the number of penals. This can be written mathematically as:

C = kN

Where C represents the cost, N represents the number of penals, and k is the constant of variation.

To find the equation that relates the cost and the number of penals, we need to determine the value of k. This can be done by using a given pair of values for C and N.

For example, if we know that when the number of penals is 5, the cost is $10, we can substitute these values into the equation:

10 = k(5)

To solve for k, we divide both sides of the equation by 5:

k = 10/5 = 2

Now we can substitute the value of k back into the equation:

C = 2N

So, the equation that relates the cost C to the number of penals N is C = 2N.