Exponential Word Problems

The population of Winnemucca, Nevada, can be modeled by P=6191(1.04)^t where t is the number of years since 1990. What was the population in 1990? 

Mathematical Equivalence

ON

The population of Winnemucca, Nevada, can be modeled by P=6191(1.04)t where t is the number of years since 1990. What percent did the population increase each year? (a)  

• 4%
• It doesn't say
• I don't know
• 400%

You have inherited land that was purchased for $30,000 in 1960. The value of the land increased by approximately 5% per year. What is the approximate value of the land in the year 2011?

• $344,022
• $31,500
• $15,000
• $28,500

Tags

CCSS.HSF.BF.A.2

During normal breathing, about 12% of the air in the lungs is replaced after one breath. Write an exponential decay model for the amount of the original air left in the lungs if the initial amount of air in the lungs is 500 mL. How much of the original air is present after 240 breaths?

• Just about zero mL
• 60 mL
• 440 mL
• 0 mL

Tags

CCSS.HSA.CED.A.1

CCSS.HSF.BF.A.1

CCSS.HSF.LE.A.1

CCSS.HSF.LE.A.2

CCSS.HSF.LE.B.5

An adult takes 400 mg of ibuprofen. Each hour, the amount of ibuprofen in the person’s system decreases by about 29%. 
What is the multiplier for this problem?

• 1.29
• .71
• .29
• 1.71

Tags

CCSS.HSF-LE.A.1C

An adult takes 400 mg of ibuprofen. Each hour, the amount of ibuprofen in the person’s system decreases by about 29%. How much ibuprofen is left after 6 hours? 

• 51 mg
• 284 mg
• 1843 mg
• 116 mg

Tags

CCSS.HSF.LE.A.4

You buy a new computer for $2100. The computer decreases by 50% annually. When will the computer have a value of $600?

• between 1 and two years
• more than 5 years
• less than a year
• between 3 and 4 years

Tags

CCSS.HSA.CED.A.1

CCSS.HSF.BF.A.1

CCSS.HSF.LE.A.1

CCSS.HSF.LE.A.2

CCSS.HSF.LE.B.5

You buy a new computer for $2100. The computer decreases by 50% annually. What would be the multiplier for this problem?

• 1.5
• .5

Tags

CCSS.HSF.BF.A.2

You drink a beverage with 120 mg of caffeine. Each hour, the caffeine in your system decreases by about 12%. How long until you have 10mg of caffeine? 

• 19 to 20 hours
• 10 to 20 hours
• 15 to 16 hours
• 5 to 6 hours

Tags

CCSS.HSF.LE.A.4

The foundation of your house has about 1,200 termites. The termites grow at a rate of about 2.4% per day. How long until the number of termites doubles?

• 29 to 30 years
• 23 to 24years
• 15 to 16 years
• 19 to 20 years

Tags

CCSS.HSF.LE.A.4