Day 3 Exponential Equations

1. Which graph represents the exponential decay of a radioactive element?

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Cassandra bought an antique dresser for $500. If the value of her dresser increases 6% annually, what will be the value of Cassandra's dresser at the end of 3 years to the nearest dollar?

• $415

• $590

• $596

• $770

The New York Volleyball Association invited 64 teams to compete in a tournament. After each round, half of the teams were eliminated. Which equation represents the number of teams, t, that remained in the tournament after r rounds?

• t = 64(r)^0.5

• t = 64(-0.5)^r

• t = 64(1.5)^r

• t = 64(0.5)^r

Kathy plans to purchase a car that depreciates (loses value) at a rate of 14% per year. The initial cost of the car is $21,000. Which equation represents the value, v, of the car after 3 years?

• v = 21,000(0.14)³

• v = 21,000(0.86)³

• v = 21,000(1.14)³

• v = 21,000(0.86)(3)

The value of a car purchased for $20,000 decreases at a rate of 12% per year. What will be the value of the car after 3 years?

• $12,800.00

• $13,629.44

• $17,600.00

• $28,098.56

A mysterious rock that decreased in size each day was found. The table to the right shows the part of the rock that remained at noon on successive days.

Which fractional part of the rock will remain at noon on day 7?

• 1/128

• 1/64

• 1/14

• 1/12

The population of Henderson City was 3,381,000 in 1994, and is growing at an annual rate of 1.8%. If this growth rate continues, what will the approximate population of Henderson City be in the year 2000?

• 3,696,000

• 3,763,000

• 3,798,000

• 3,831,000

Which the following graphs shows an exponential decay equation?

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Tags

CCSS.HSF-IF.C.7E

A certain type of bacteria decays at a rate of 1/4 of its size per day. A scientist starts with 80 mg of this bacteria.

Write an exponential equation to show this decay.

• y = (1/4)x

• y = 1/4(80)^x

• y = (80)(1/4)(x)

• y = 80(1/4)^x

Tags

CCSS.HSF.LE.A.2

Can you convert this function table into an equation? Let's see!

X | Y

0 | 2

1 | 10

2 | 50

3 | 250

4 | 1250

• y = 2(10)^x

• y = 2(5)^x

• y = 5(2)^x

• y = 5(10)^x

Tags

CCSS.HSF.LE.A.2