Standard 25: Exponential Decay Mastery Check

Master exponential decay! Practice identifying rates, writing equations, and calculating values in real-world scenarios.

1. Match the following exponential equations with its appropriate situation. Each equation will match with exactly one situation. Remember, when calculating the decay rate, it is 1 - r. So if the decay rate is 40%, then 1 - 0.4 = 0.6. Click HERE to see how to match. 2a. You purchase a new Xbox Series X for $700. It is expected that this Xbox will lose roughly 12% of its value each year that you own it. What is the initial value in this situation? Please either type your work, take a picture of your work and upload it, or use the voice recording to talk through how you arrived at your answer. 2b. Using the same situation from 2a, what is the rate of decay? Please either type your work, take a picture of your work and upload it, or use the voice recording to talk through how you arrived at your answer. 2c. What is the equation that would model the situation from 2a? Please either type your work, take a picture of your work and upload it, or use the voice recording to talk through how you arrived at your answer. 2d. How much will the Xbox be worth after 5 years? Please either type your work, take a picture of your work and upload it, or use the voice recording to talk through how you arrived at your answer. 3a. You are drinking a beverage that has 180 mg of caffeine in it. Each hour, the caffeine in your system decreases by 14%. Write an equation that models this situation. Please either type your work, take a picture of your work and upload it, or use the voice recording to talk through how you arrived at your answer. 3b. Using the equation you made in 3a, how much caffeine will be in your system after 3 hours? 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! Scroll down to make sure you have confirmed your work or your teacher will be unable to see what you have done!