5/7 Exponential Decay

First, click HERE to watch a video explaining today's activity and some examples of what you are about to do. 1. Below is the formula for exponential decay. Click on the blue dots and identify the meaning of each component of the equation as one of the following: time intervals, initial value, decay rate. 2. Given y = 210(0.88)x what is the initial / starting value? 3. Given y = 210(0.88)x what is the decay rate? In other words, what is the percent of decrease? Remember, the decay rate is just the "r" value. 4. Evaluate y = 210(0.88)x when x = 3. In other words, what is the value of the equation when you substitute 3 in for the x variable. Please either type your work below, write out your work on a separate piece of paper, or voice record yourself explaining your work. 5. Before quarantine, you bought a jumbo sized bag of candy that had 14,000 pieces in it. You decide to eat 8% of the bag each day. Write an exponential equation in the form y = a(1 - r)x that models this situation. 6. Using your equation from #5, how much candy is left in the bag after 6 days? That is, with the time interval (x value) being 6, what is the y value? Please either type your work below, write out your work on a separate piece of paper, or voice record yourself explaining your work. 7. Your friend with lice in her hair decides to treat her hair with special shampoo. After seeing the doctor, it was determined she had 60 lice in her hair and the shampoo she is using will kill 10% of the lice each day. Write an exponential equation in the form y = a(1 - r)x that models this situation. 8. Using your equation from #7, determine how many lice will still be in your friends hair after 7 days of using the shampoo. Please either type your work below, write out your work on a separate piece of paper, or voice record yourself explaining your work. Select one of the choices below that best describe how you feel after today's lesson. Great job! You've made it to the end. Be sure to click the "Hand in Work" button TWICE! The first time you click it, it will ask you to confirm your work. Then, you must click "Confirm Hand In Work" to submit your responses!