Growth and Decay Word Problems

An air freshener starts with 30 grams of fluid, and the amount of fluid decreases by 12% per day. Express the amount of grams of freshener, Q, that remains, t, days after it has begun being used.

Check the BEST answer: (HINT: that means simplify what is in the parenthesis)

• Q=30(1+0.12)^t

• Q=30(1-0.12)^t

• Q=30(0.88)^t

• Q=12(1.30)^t

What is the initial quantity?

What is the DECAY rate? Write as a percent! CAREFUL!!!

You start an account with $500 and an interest rate of 6% compounded yearly. How much is in the account after 3 years?

Round to the nearest cent. (two decimal places)

From 2000 - 2010 a city had a 2.5% annual decrease in population. If the city had 2,950,000 people in 2000, determine the city’s population in 2008.

Round to the nearest..... (these are people)... so whole number!

You buy a car for $8000 that depreciates at a rate of 11% a year. How much is the car worth after 5 years?

Round to the nearest cent. (two decimal places)

3.1(0.78)^t

Is the function growth or decay?

Check the box:

• Growth

• Decay

The population of a school is 800 students and is increasing at a rate of 2% per year. Use an exponential function to find the population of the school after 9 years.

Round to the nearest whole number.

• Initial amount

• Rate of growth or decay

• Time

• End amount

Annual sales for a fast food restaurant are $650,000 and are increasing at a rate of 4% per year. Use an exponential function to find the annual sales after 7 years.

Round to two decimal places (like dollars and cents).