Maap Assessment Growth and Decay Word Problem

During a certain period of time, about 70 northern sea otters had an annual growth of 18%. Use an exponential function to find the number of sea otters after 4 years.

Round to the nearest whole number.

A population of fish starts at 8,000 and decreases by 6% per year. Use an exponential function to find the population of fish in 10 years.

Round to the nearest whole number.

Twenty years ago, Mr. Davis purchased his home for $160,000. Since then, the value of the home has increased about 5% per year. Use an exponential function to find the value of the home today.

Round to two decimal places (like money).

• Initial amount

• Rate of growth or decay

• Time

• End amount

North Dakota has recently had the fastest growing population out of all 50 states. On Jan 1, 2013, the population of North Dakota was 700,000 people. North Dakota’s population has been growing by 5% per year. Express North Dakota’s population, N, in terms of years since 2013, t. Check the BEST answer:

• N=700,000(1.05)t

• N=700,000(1.5)t

• N=700,000(1-0.05)^t

• N=700,000(0.95)^t

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 DECAY rate?

Write as a percent!

CAREFUL!!!

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)

Nathan bought a VERY fancy boat for about $125,000. If the boat's value depreciates at the rate of 15% per year, what is the value of the boat at the end of 10 years?

• $12,512.50

• $18,750

• $24,609.30

• $505,694.72