Question 1172664
<br>
11% is lost each year, so each year the amount remaining is 100-11 = 89% of the amount at the beginning of the year.  So the amount remaining gets multiplied by 89% = 0.89 each year.<br>
So starting with 530 grams, after t years the amount remaining is<br>
{{{530(0.89)^t}}}<br>
The portion remaining after a quarter of a year is, to a few decimal places,<br>
{{{0.89^(1/4) = 0.971287}}}<br>
So the decrease per quarter is<br>
{{{1-.971287 = 0.028713}}}<br>
or 2.87%.<br>