Download 8.3 Part 2 Modelling Exponential Functions Worksheet

PC 12
8.3 Part 2 Modelling Exponential Functions Worksheet
Name: _____________________________
Date: _________________________
Block: ________
1. A city with a population of 828,500 grows at a rate of 2.2% a year. How many years would it take the
population to grow to 1 million?
2. A cell phone battery loses 2% of its charge a day. If the battery is fully charged right now, how many
days will it take until the battery is only 50% charged?
3. Calculate the number of years for an investment of $1000 to double at each interest rate.
a. 7.2% compounded annually
b. 6.97% compounded monthly
4. Polonium-210 is a radioactive element with a half-life of 20 weeks. From a sample of 25 g, how much
would remain after 14 weeks?
5. An element decays from 200 g to 170 g in 7 weeks. Determine the half-life of the element?
6. A population of a swarm of locusts can multiply tenfold in 3 weeks. Suppose there are 2000 locusts
right now. How many will there be after 8 weeks?
PC 12
8.3 Part 2 Modelling Exponential Functions Worksheet
Name: _____________________________
Date: _________________________
Block: ________
1. A city with a population of 828,500 grows at a rate of 2.2% a year. How many years would it take the
population to grow to 1 million?
2. A cell phone battery loses 2% of its charge a day. If the battery is fully charged right now, how many
days will it take until the battery is only 50% charged?
3. Calculate the number of years for an investment of $1000 to double at each interest rate.
b. 7.2% compounded annually
b. 6.97% compounded monthly
4. Polonium-210 is a radioactive element with a half-life of 20 weeks. From a sample of 25 g, how much
would remain after 14 weeks?
5. An element decays from 200 g to 170 g in 7 weeks. Determine the half-life of the element?
6. A population of a swarm of locusts can multiply tenfold in 3 weeks. Suppose there are 2000 locusts
right now. How many will there be after 8 weeks?
7. How many times more intense is an earthquake of magnitude 6.2 than one with magnitude 5.5?
8. Given the magnitude of one earthquake is 6.5, determine the magnitude of a second earthquake that is
3 times the intensity as the first.
9. Textbook questions p. 401 # 13 – 16
Answers
1. ~8.65 yrs
5. ~29.86 wks
2. ~34 days
3a. 10 yrs
6. ~928,318 locusts
b. 10 yrs
7. ~ 5 times
4. 15.4 g
8. ~6.98
7. How many times more intense is an earthquake of magnitude 6.2 than one with magnitude 5.5?
8. Given the magnitude of one earthquake is 6.5, determine the magnitude of a second earthquake that is
3 times the intensity as the first.
9. Textbook questions p. 401 # 13 – 16
Answers
2. ~8.65 yrs
5. ~29.86 wks
2. ~34 days
3a. 10 yrs
6. ~928,318 locusts
b. 10 yrs
7. ~ 5 times
4. 15.4 g
8. ~6.98