Finding Common Ratios in Real-Life Sequences

A plant grows 2 inches in the first week and then doubles its height each subsequent week. If the plant is 2 inches tall at the start, what will its height be after 4 weeks?

• 4 inches

• 32 inches

• 16 inches

• 8 inches

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

• $10,000

• $7,680

• $8,500

• $9,600

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

• 2400

• 4000

• 3200

• 1600

A savings account earns interest at a rate of 5% compounded annually. If you start with $1,000, how much will you have after 4 years?

• 1500.00

• 1300.00

• 1100.00

• 1215.51

A video game character earns 50 points in the first level and then earns 1.5 times the points in each subsequent level. How many points will the character earn in the 6th level?

• 379.6875

• 300 points

• 500 points

• 150 points

A tree grows 3 feet in the first year and then grows 1.5 times its height each following year. If the tree is 3 feet tall at the end of the first year, how tall will it be at the end of the 5th year?

• 18 feet

• 12.5 feet

• 10 feet

• 15.19 feet

A company’s profit increases by a factor of 1.2 each year. If the profit was $10,000 last year, what will it be in 3 years?

• $12,000

• $17,280

• $20,000

• $15,000

A recipe calls for 2 cups of flour, and each time you double the recipe, how much flour will you need for 5 batches?

• 8 cups of flour

• 12 cups of flour

• 15 cups of flour

• 10 cups of flour

A phone plan costs $30 for the first month and then increases by 10% each month. How much will the plan cost in the 6th month?

• $42.00

• $36.00

• $55.00

• $48.31

A population of fish in a lake is 500 and increases by a factor of 1.3 each year. What will the population be after 4 years?

• 1200

• 1428

• 800

• 1600