Exponential Problems [4.26]

An experiment begins with 20 grams of a radioactive isotope. This isotope has a half-life. If y is the mass in grams remaining after x half-lives have elapsed, which equation represents the amount of grams the isotope will weigh after 4 half-lives?

The number of turkey vultures in a nature sanctuary is doubling each year. When the sanctuary opened, it was home to 204 turkey vultures. Which equation can be used to find the number of turkey vultures after x years?

Tags

CCSS.HSF.LE.A.2

A population of ants increases by a factor of 5 each year. Initially there were 450 aunts. Which equation represents the amount of aunts after 9 years?

Let y represent the total amount of aunts after x years.

Tags

CCSS.HSF.LE.A.2

You have 40 grams of a radioactive kind of silver. How much will be left after 14 days if it triples each day?

*Use Google Calculator and shift 6 to get the exponent.

• 191,318,760

• 109,760

• 18,130,406

• 14000

The population of wild yellow-eyed baboons living in a forest quadruples every year. If there are 24 baboons living in the forest today, how many will there be in 3 years?

*Use google calculator.

• 1,944

• 55,296

• 192

• 1,536

Annual sales for a fast food restaurant are $650,000 and are increasing at a factor of 1.04 per year. Use an exponential function to find the annual sales after 7 years.

• $1,000,124

• $4,030

• $855,355.66

• $434,505.66

You have inherited land that was purchased for $30,000 in 1960. The value of the land increased by approximately 5% per year. Write an equation to represent the situation:

Tags

CCSS.HSF-BF.A.1A

Is y = 54(.20)^x growth or decay?

• Growth because of the 54
• Decay because of the .20
• Decay because of the 54
• Growth because of the .20

Tags

CCSS.HSF-IF.C.8B

You have inherited land that was purchased for $30,000 in 1990. The value of the land increased by approximately 5% per year. What is the approximate value of the land in the year 2011?

• $83,579
• $10,217
• $14,963,655
• $28,500

Tags

CCSS.HSF.BF.A.2

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?

• 104%
• 4%
• 40%
• 400%

Tags

CCSS.HSF-LE.A.1C