Finding outputs of a one-step function that models a real-world situation

In this lesson, we have one-step functions modeling real world problems. In such cases we find outputs of those functions.

After eating at a restaurant, Joe, Tom, Bill and Sunny decided to divide the bill evenly. If the total bill given by the function A(x) = 4x amounted to $136, how much should each pay(x)?

Solution

Step 1:

Total bill amount A(x) = 4x = $136

Step 2:

$\frac{4x}{4}$ = $ $\frac{136}{4}$

So x = $34

Shania is baking a cake. The recipe calls for C(y) = y + 3 cups of flour. How many cups does she need if y = 5 cups?

Solution

Step 1:

Cups of flour, C(y) = y + 3 cups; y = 5

Step 2:

C(y) = y + 3 = 5 + 3 = 8

So C(5) = 8 cups