Grade 9 Exponential Equations & Graphs Challenge

A population of bacteria doubles every 3 hours. If there are initially 500 bacteria, how many will there be after 12 hours? Solve the exponential equation and graph the function.

• 6000

• 10000

• 8000

• 4000

A car's value decreases by 20% each year. If the car is currently worth $15,000, what will its value be after 5 years? Solve the exponential equation and describe the graph.

• $7,500

• $10,000

• $4,915.20

• $2,000

A bank offers an interest rate of 5% compounded annually. If you deposit $1,000, how much will you have after 10 years? Solve the exponential equation and graph the growth of your investment.

• $2,000.00

• $1,500.50

• $1,200.00

• $1,628.89

A certain species of fish in a lake grows exponentially. If the current population is 200 and it increases by 50% each year, what will the population be in 4 years? Solve the equation and sketch the graph.

• 800

• 600

• 1200

• 1013

A tree grows at a rate of 10% per year. If the tree is currently 3 feet tall, how tall will it be in 6 years? Solve the exponential equation and illustrate the growth on a graph.

• Approximately 5.31 feet

• Approximately 6.00 feet

• Approximately 4.00 feet

• Approximately 7.50 feet

A certain type of radioactive substance has a half-life of 5 years. If you start with 80 grams, how much will remain after 15 years? Solve the exponential equation and graph the decay.

• 40 grams

• 20 grams

• 10 grams

• 5 grams

A smartphone's battery life decreases exponentially. If it starts at 100% and loses 15% each hour, what will the battery percentage be after 4 hours? Solve the equation and graph the battery life over time.

• 30.25%

• 45.00%

• 70.50%

• 52.20%

A savings account has an initial deposit of $2,000 and earns 3% interest compounded monthly. How much will be in the account after 3 years? Solve the exponential equation and graph the account balance over time.

• $1,800.50

• $2,186.89

• $2,500.00

• $2,000.00

A viral video on social media gains views exponentially. If it starts with 1,000 views and doubles every day, how many views will it have after 7 days? Solve the equation and create a graph of the views over the week.

• 256000 views

• 64000 views

• 50000 views

• 128000 views

A certain plant species grows exponentially, starting with 50 plants and increasing by 30% each month. How many plants will there be after 6 months? Solve the exponential equation and graph the growth trend.

• 300

• 186

• 150

• 220