If there are n children, and each additional child who joins will add another $6 to the cost, then the cost due to the number of children will be 6n. We also have the fixed cost of $60, no matter how many children join. Therefore, we add up these costs to get Cost = f(n) = 60 + 6n.
the first number is 57 to the ninth power and the second is 19 to the third power, not to sure about the dividing but a quick google search should do the trick
