Question 633075
You are correct in using a volume formula and plugging in given values. The problem is you used the wrong volume formula and therefore had to plug in your values for the wrong variables. The formula you used, V=s^2*h, is for a rectangular prism with a square base. This coal bin has a rectangular base- it has 3 different dimensions instead of having 2 that are equal. So you need the formula Volume=length*width*height, or in this case, Volume=length*width*depth. Now let's plug in our values.
V=l*w*d
60=5*4*d
60=20*d
60/20=d
3=d
The bin must be filled to a depth of 3 meters.