Exponential growth and decay

A party charges $5 admission for each person.

• Linear
• Exponential
• Neither

The value of a painting is $12,000 in 1990 and increases by 8% of its value each year.  Write and evaluate an expression to estimate the paintings value in 2005.

• 1.08(12,000)^t = $36,000
• 12,000(1.08)^t = $38, 066
• 12,000(0.5)^t = $10,000
• 12,000(0.92)^t = $40,000

A 78 gram sample of Uranium loses half of its mass each year.  How much is left after 6 years?

• 13 grams
• 6.5 grams
• 1.22 grams
• 592.31 grams

James' 70 in. giant peach doubles in size every week. Write an expression that would represent how big the peach is after 5 weeks.

• 70(2)³⁵
• 70(2)⁵
• 2(70)⁵
• 5(70)²

The attendance at the art museum at the New Year’s opening was 250 people. The attendance has been increasing at a rate of 3% each month. How many people will attend by the end of a year?

• 356
• 265
• 5825
• 1329

What is a, the starting term, for the function: f(x) = 800(0.85)^x?

• 800
• 0.85
• 0.15
• x

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x
• y = 15(1.35)^x
• y = 15(0.35)^x
• y = 35(1.15)^x

A population of fish starts at 8,000 and decreases by 6% per year. What is the population of fish after 10 years?

• 14327
• 4309
• 839
• 7680

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x
• y=30(5000)^x
• y=5000(1.3)^x
• y=5000x^x

What does the model P=A(1+r)^t best represent?

• Exponential growth
• Simple Interest
• Compound Interest
• Exponential Decay