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How do you find out how much time it will take the money in your bank account to double? For example: I f you have $100 in the bank, how long until you earn $100 interest?. In this lesson you will learn how to create and solve exponential equations by using a table of values. Example:
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How do you find out how much time it will take the money in your bank account to double? For example: If you have $100 in the bank, how long until you earn $100 interest?
In this lesson you will learn how to create and solve exponential equations by using a table of values
Example: You start with 25 dots, and the number of dots increase by 40% in every step. 40% growth 40% growth
y = a(1+r)x y = 25(1+.4)x 40% growth 40% growth y = 25(1.4)x
Growth Factor > 1 (example 1.4) 0 < Decay Factor < 1 (example 0.4)
Your bank account has grown according to the data shown in the table. Write an equation and find out how long your account will take to reach a balance of $600?
y = a(1+r)x y = (400)*(1+r)x y = (400)*1.06x 600 = (400)*1.06x x ≈ 7 years VERIFY: what does my answer mean? does this make sense?
In this lesson you have learned how to create and solve exponential equations by using a table of values
When you buy a new car, its value quickly “depreciates”, or, loses value according to the data seen here. Approximately how long will it take for your car’s value to fall to $13000?
y = a(1+r)x y = (25000)*(1+r)x y = (25000)*.85x 13000 = (25000)*.85x x ≈ 4 years VERIFY: what does my answer mean? does this make sense?
Investigate the interest rates of a few different bank accounts and evaluate which is a better account for your money. Don’t forget to look for monthly vs. annually compounding interests! • Explore the math function called “logarithm”, and investigate how the “logarithm” can help you solve exponentials.
1. Your bank account is compounded 6% annually (every year). If you put $500 to start, in how many years will your bank account reach $1000? 2. Polar bear populations have been on the decline recently. If the population is decreasing at a rate of 13% each year, how long will it take an original population of 7000 to reach 4000?