Growth/Decay and Compound Interest

What is the formula for exponential growth?

Tags

CCSS.HSF-IF.C.8B

What is the formula for exponential decay?

Tags

CCSS.HSF-IF.C.8B

Convert the percent to a decimal:

9%=

• .9

• 900

• .009

• .09

Convert the percent to a decimal. Remember: move the decimal two places to the left!

3.5%=

• .35

• 3.5

• .035

• .0035

Middletown High School has student elections every year. Lately, the school has seen a 5% decrease in voting from election to election. If 910 students voted this year, how many will be expected to vote 8 years from now? (Round to the nearest whole number if necessary).

• 604

• 777

• 29

• 198

Tags

CCSS.HSF-LE.A.1C

More and more people are purchasing food from farmers' markets. As a consequence, a market researcher predicts that the number of farmers' markets will increase by 15% each year. If there are 6,200 farmers' markets this year, how many will there be in 10 years? (Round to the nearest whole number if necessary).

• 25,082

• 12,937

• 62,000

• 43,511

Tags

CCSS.HSF-LE.A.1C

A publishing industry report predicts that magazine subscriptions will drop by 10% each year. If this prediction is correct, then how many subscribers will a magazine with 98,000 subscribers have in 10 years? (Round to the nearest whole number if necessary).

• 34,170

• 16,348

• 7690

• 76,023

Tags

CCSS.HSF.BF.A.2

Jenny has $20 in a savings account. The interest rate is 5%, compounded annually. To the nearest cent, how much interest will she earn in 2 years?

• $2.05

• $45.79

• $1.99

• $7.51

Tags

CCSS.HSF-LE.A.1C

A cliff overlooking Oak Grove Lake is experiencing erosion, losing elevation at a rate of 5% every millennium. The cliff's current elevation is 1,200 meters. What will its elevation be in 6 millennia? (Round to the nearest whole number if necessary).

• 882

• 465

• 349

• 975

Tags

CCSS.HSF-LE.A.1C

In 1985, there were 285 cell phone subscribers in Mayville. The number of subscribers increased by 75% per year after 1985. How many subscribers were in Mayville in 2008? (Verbal Question: What word tells us this is growth or decay?)

• 110,845,988

• 111, 043,298

• 109,678,401

• 110,544,827

Tags

CCSS.HSF-LE.A.1C