Functions and Real-World Applications

This video tutorial explains how to write function rules for different scenarios. It covers four examples: adjusting cellphone plan costs, calculating sale prices with discounts, determining meal prices with discounts, and dividing pizzas among people. Each example demonstrates how to use function notation to express the relationship between inputs and outputs, providing a clear understanding of how to apply function rules in practical situations.

What is the main focus of this lesson?

• Writing essays

• Solving equations

• Writing function rules

• Learning history

If the current monthly cost of a cellphone plan is $20, what will be the new cost after the increase?

• $30

• $25

• $20

• $15

How do you express the new monthly cost as a function of the current cost?

• M(C) = C - 5

• M(C) = C * 5

• M(C) = C / 5

• M(C) = C + 5

What percentage of the original price do you pay after a 15% discount?

• 85%

• 50%

• 15%

• 100%

How is the sale price expressed as a function of the original price?

• S(P) = 1.15P

• S(P) = P + 0.15

• S(P) = 0.15P

• S(P) = 0.85P

What is the discounted meal price if the original price is $50?

• $45

• $40

• $60

• $50

How do you express the discounted meal price as a function of the original price?

• D(M) = M - 10

• D(M) = M + 10

• D(M) = M * 10

• D(M) = M / 10

If 4 pizzas are shared among 8 people, how much pizza does each person get?

• 1/2 of a pizza

• 2 pizzas

• 1 pizza

• 1/4 of a pizza

How is the amount of pizza each person gets expressed as a function of the number of people?

• A(X) = 4 * X

• A(X) = 4 / X

• A(X) = X / 4

• A(X) = X - 4

If only 1 person shows up to the party, how many pizzas do they get?

• 1 pizza

• 2 pizzas

• 3 pizzas

• 4 pizzas