Real-World Applications of Geometric Sequences for 8th Graders

A bacteria culture doubles in size every hour. If there are initially 100 bacteria, how many will there be after 5 hours?

• 3200

• 1600

• 4000

• 2400

A car's value depreciates by 20% each year. If the car is worth $15,000 now, what will its value be in 3 years?

• $5,000

• $12,000

• $10,000

• $7,680

A tree grows 1.5 times its height each year. If it is currently 2 meters tall, how tall will it be after 4 years?

• 8.0 meters

• 12.0 meters

• 5.5 meters

• 10.125 meters

A savings account earns interest at a rate of 5% compounded annually. If you start with $1,000, how much will you have after 3 years?

• 1157.63

• 1200.00

• 1050.25

• 1100.50

A video game character gains experience points in a geometric sequence: 50, 100, 200, ... If this pattern continues, how many points will the character have after 6 levels?

• 1800

• 3150

• 4000

• 2500

A company’s profits increase by 10% each year. If the profit this year is $200,000, what will it be in 5 years?

• $300,000

• $400,000

• $322,102.50

• $250,000

A geometric sequence starts with 3 and has a common ratio of 4. What is the 6th term of this sequence?

• 3072

• 512

• 768

• 1024

A population of fish in a lake triples every year. If there are currently 200 fish, how many will there be after 3 years?

• 1200

• 800

• 600

• 5400

A cell phone plan offers a discount that reduces the monthly fee by 15% each year. If the current fee is $60, what will it be in 2 years?

• $36.00

• $51.00

• $43.35

• $48.75

A geometric sequence has a first term of 5 and a common ratio of 2. What is the sum of the first 4 terms of this sequence?

• 75

• 50

• 100

• 30