EXPONENTIAL GROWTH & DECAY LT 3.3 - I CAN DETERMINE WHETHER AN EXPONENTIAL FUNCTION HAS RATE THAT IS A GROWTH FACTOR OR A DECAY FACTOR. LT 3.4 - I CAN COMPARE THE GRAPHS, EQUATIONS AND TABLES OF EXPONENTIAL FUNCTIONS

Exponential Growth Formulas Use y = a(b)x when given terms like doubling (b=2), tripling (b=3), or when you see the words “growth factor” Use y=a (1 + r)x when given a percentage growth rate. Convert % to a decimal by dividing it by 100%. Ex. 25% growth rate with an initial value of 3: 25%/100%=.25 y = 3(1+.25)x y = 3(1.25)x

Since 2005, the amount of money spent at restaurants in the US has increased about 7% each year. In 2005, about $360 billion was spent at restaurants. How much will be spent at restaurants this year (2017) ?  

You invest $100 and expect your money to grow 8% each year You invest $100 and expect your money to grow 8% each year. About how many years will it take for your investment to double?  

Exponential Decay Formulas Use y = a(b)x when given terms like half (b=1/2) or when you see the words “decay factor” Use y=a (1 - r)x when given a percentage decay or depreciation rate. Convert % to a decimal by dividing it by 100%. Ex. 25%decay rate with an initial value of 3: 25%/100%=.25 y = 3(1-.25)x y = 3(.75)x

The kilopascal is a unit of measure for atmospheric pressure The kilopascal is a unit of measure for atmospheric pressure. The atmospheric pressure at sea level is about 101 kilopascals. For every 1000-m increase in altitude, the pressure decreases about 11.5%. What is the approximate pressure at an altitude of 3000-m?  

A family buys a car for $20,000. The value of the car decreases about 20% each year. After 6 years, the family decided to sell the car. Should they sell it for $4,000?  

Half-life Problems