The elevation of a mountain is 27,370 feet. Due to erosion, this mountain is reduced by 0.2% each year. In how many years will the elevation be 26,986.82 feet?

1 answer

Let x be the number of years it takes for the elevation to be 26,986.82 feet.

First, calculate the erosion amount per year:
0.2% of 27,370 = 0.002 * 27,370 = 54.74 feet

Then, set up the equation:
27,370 - 54.74x = 26,986.82

Solve for x:
54.74x = 27,370 - 26,986.82
54.74x = 383.18
x = 383.18 / 54.74
x = 7 years

Therefore, it will take 7 years for the elevation of the mountain to be 26,986.82 feet.