Solving Real-World Problems: Variables & Substitution

Maria and John are saving money for a concert. Maria saves $15 each week, while John saves $10 each week. If they want to save a total of $150 together, how many weeks will it take for them to reach their goal? Use the substitution method to find the solution.

• 8 weeks

• 5 weeks

• 7 weeks

• 6 weeks

A farmer has chickens and cows. The total number of animals is 50, and the total number of legs is 140. How many chickens and how many cows does the farmer have? Identify the dependent and independent variables in this scenario.

• 10 chickens and 40 cows

• 20 chickens and 30 cows

• 25 chickens and 25 cows

• 15 chickens and 35 cows

A local gym charges a $50 membership fee plus $5 per class. If a member pays a total of $100, how many classes did they attend? Use the substitution method to solve the problem.

• 15

• 5

• 10

• 20

In a bookstore, the price of a novel is $12 and the price of a magazine is $5. If a customer buys a total of 10 items and spends $80, how many novels and magazines did they buy? Identify the dependent and independent variables.

• 2 novels and 8 magazines

• 5 novels and 5 magazines

• 3 novels and 7 magazines

• 4 novels and 6 magazines

A car rental company charges a flat fee of $30 plus $0.20 per mile driven. If a customer pays $50, how many miles did they drive? Use the substitution method to find the answer.

• 120 miles

• 50 miles

• 100 miles

• 75 miles

Two friends, Alex and Jamie, are selling lemonade and cookies. Alex sells lemonade for $2 per cup and Jamie sells cookies for $1 each. If they together earn $50 and sell 30 items, how many cups of lemonade and cookies did they sell? Identify the dependent and independent variables.

• Alex sold 25 cups of lemonade and Jamie sold 5 cookies.

• Alex sold 15 cups of lemonade and Jamie sold 15 cookies.

• Alex sold 20 cups of lemonade and Jamie sold 10 cookies.

• Alex sold 10 cups of lemonade and Jamie sold 20 cookies.

A concert hall has two types of tickets: regular tickets for $25 and VIP tickets for $50. If 200 tickets are sold for a total of $8000, how many of each type of ticket were sold? Use the substitution method to solve the problem.

• 90 regular tickets and 110 VIP tickets were sold.

• 100 regular tickets and 100 VIP tickets were sold.

• 80 regular tickets and 120 VIP tickets were sold.

• 150 regular tickets and 50 VIP tickets were sold.

A gardener is planting flowers and shrubs. Each flower costs $3 and each shrub costs $5. If the gardener buys a total of 20 plants and spends $60, how many flowers and shrubs did they buy? Identify the dependent and independent variables.

• 15 flowers and 5 shrubs.

• 10 flowers and 10 shrubs.

• 5 flowers and 15 shrubs.

• 20 flowers and 0 shrubs.

A bakery sells muffins for $2 each and cookies for $1 each. If a customer buys a total of 15 items and spends $24, how many muffins and cookies did they buy? Use the substitution method to find the solution.

• 9 muffins and 6 cookies

• 10 muffins and 5 cookies

• 8 muffins and 7 cookies

• 7 muffins and 8 cookies