Answer: first choice: 1/5
Step-by-step explanation:
An important feature of exponential functions is that they have a constant multiplicative rate of change.
The multiplicative rate of change is the ratio between two consecutiive terms. This is because every term is obtained by multiplicating the previous term by such constant rate.
Hence, you find the multiplicative rate of change by dividing any term by the previous one.
Here is what you obtain in this case:
- Second term / first term = (2/5) ÷ 2 = (2×1) ÷ (2×5) = 1/5
- Third term / second term = (2/25) ÷ (2/5) = (2×5) ÷ (2×25) = 1/5
- Fourt term / third term = (2/125) ÷ (2/25) = (2×25) ÷ (2×125) = 1/5
Hence, the multiplicative rate of change is the first choice: 1/5