A conservationist determines that a particular beach is eroding at a rate of 1.1% each year. When writing an explicit formula to represent the amount of beach remaining each year, which value should she use as the common ratio?

0.011
0.089
0.989
1.011

Question

A conservationist determines that a particular beach is eroding at a rate of 1.1% each year. When writing an explicit formula to represent the amount of beach remaining each year, which value should she use as the common ratio? 

 0.011
0.089
0.989
1.011

tkhunny · Answer

Erosion Rate = 1.1% = 0.011
Stable Rate = 1 - Erosion Rate = 1 - 0.011 = ??

f(0) = 1
f(1) = 1 * Stable Rate
f(2) = 1 * (Stable Rate)^2

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