Explanation of the Solution

aaronhma

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quacker88

Well, from the video, we know that at the start of the year 2110, the foundation has $$100,000$ left. We also knows that the foundation gives away $$100,000$ each year! This means that the foundation will give away this exact sum of $$100,000$ that they have right now, spread evenly over the course of one year. Since 2110 has 365 days, each day, they give away $\frac{100,000}{365}=$ $$ 273.97$. What might have confused you is that in the solution, it's almost like counting backwards.

Since the foundation gives away $$ 273.97$ per day, the amount they have given away is
$273.97 \cdot (\text{number of days that have passed in the year)} $.

This means that the amount they have left is
$273.97 \cdot (\text{number of remaining days in the year)} $.

So, since there are 31 days remaining, the foundation has
$273.97\cdot31=$ $$8493$ left.

Hope this helps

aaronhma

This post is deleted!