Based on the image you provided, this is an “Exponential Growth and Decay Worksheet” where you are asked to analyze several exponential functions of the form `y = a * b^x`.
The circled problems are:
1.
y = 0.32(0.98)^x
2.
y = 0.775(1.04)^x
3.
y = 14,000(0.92)^x
For each of these, you need to answer three questions:
-
a. Does the function represent exponential growth or exponential decay?
-
b. What is your initial value?
-
c. What is the rate of growth or rate of decay?
---
🔍 General Rules for Exponential Functions: y = a * b^x
-
Initial Value (a): This is the value of `y` when `x = 0`. So, `a` is always the initial value.
-
Growth vs. Decay:
- If `b > 1`, the function represents
exponential growth.
- If `0 < b < 1`, the function represents
exponential decay.
-
Rate of Growth/Decay:
- For
growth: Rate = `(b - 1) * 100%`
- For
decay: Rate = `(1 - b) * 100%`
---
##
✔ Problem 1: y = 0.32(0.98)^x
-
a. Growth or Decay?
- Base `b = 0.98`
- Since `0 < 0.98 < 1`, this is
exponential decay.
-
b. Initial Value?
- `a = 0.32`
- So,
initial value = 0.32
-
c. Rate of Decay?
- Rate = `(1 - b) * 100% = (1 - 0.98) * 100% = 0.02 * 100% = 2%`
- So,
rate of decay = 2%
> 📌
Answer for #1:
> a. Exponential decay
> b. 0.32
> c. 2%
---
##
✔ Problem 2: y = 0.775(1.04)^x
-
a. Growth or Decay?
- Base `b = 1.04`
- Since `1.04 > 1`, this is
exponential growth.
-
b. Initial Value?
- `a = 0.775`
- So,
initial value = 0.775
-
c. Rate of Growth?
- Rate = `(b - 1) * 100% = (1.04 - 1) * 100% = 0.04 * 100% = 4%`
- So,
rate of growth = 4%
> 📌
Answer for #2:
> a. Exponential growth
> b. 0.775
> c. 4%
---
##
✔ Problem 3: y = 14,000(0.92)^x
-
a. Growth or Decay?
- Base `b = 0.92`
- Since `0 < 0.92 < 1`, this is
exponential decay.
-
b. Initial Value?
- `a = 14,000`
- So,
initial value = 14,000
-
c. Rate of Decay?
- Rate = `(1 - b) * 100% = (1 - 0.92) * 100% = 0.08 * 100% = 8%`
- So,
rate of decay = 8%
> 📌
Answer for #3:
> a. Exponential decay
> b. 14,000
> c. 8%
---
##
✔ Final Answers Summary:
| Problem | Function | a. Type | b. Initial Value | c. Rate |
|---------|--------------------|-----------------|------------------|-------------|
| 1 | y = 0.32(0.98)^x | Decay | 0.32 | 2% |
| 2 | y = 0.775(1.04)^x | Growth | 0.775 | 4% |
| 3 | y = 14,000(0.92)^x | Decay | 14,000 | 8% |
You can now fill in these answers on your worksheet! Let me know if you’d like help with the other problems too.
Parent Tip: Review the logic above to help your child master the concept of exponential functions growth and decay worksheet.