I only got 22-25 done cause its been a long time since ive done these so i don't remember how to do the first two ):
The area <em>A</em> of a trapezoid with height <em>h</em> and bases <em>b</em>₁ and <em>b</em>₂ is equal to the average of the bases times the height:
<em>A</em> = (<em>b</em>₁ + <em>b</em>₂) <em>h</em> / 2
We're given <em>A</em> = 864, <em>h</em> = 24, and one of the bases has length 30, so
864 = (<em>b</em>₁ + 30) 24 / 2
864 = (<em>b</em>₁ + 30) 12
864 = (<em>b</em>₁ + 30) 12
72 = <em>b</em>₁ + 30
<em>b</em>₁ = 42
The coefficient of determination can be found using the following formula:
![r^2=\mleft(\frac{n(\sum ^{}_{}xy)-(\sum ^{}_{}x)(\sum ^{}_{}y)}{\sqrt[]{(n\sum ^{}_{}x^2-(\sum ^{}_{}x)^2)(n\sum ^{}_{}y^2-(\sum ^{}_{}y)^2}^{}}\mright)^2](https://tex.z-dn.net/?f=r%5E2%3D%5Cmleft%28%5Cfrac%7Bn%28%5Csum%20%5E%7B%7D_%7B%7Dxy%29-%28%5Csum%20%5E%7B%7D_%7B%7Dx%29%28%5Csum%20%5E%7B%7D_%7B%7Dy%29%7D%7B%5Csqrt%5B%5D%7B%28n%5Csum%20%5E%7B%7D_%7B%7Dx%5E2-%28%5Csum%20%5E%7B%7D_%7B%7Dx%29%5E2%29%28n%5Csum%20%5E%7B%7D_%7B%7Dy%5E2-%28%5Csum%20%5E%7B%7D_%7B%7Dy%29%5E2%7D%5E%7B%7D%7D%5Cmright%29%5E2)
Using a Statistics calculator or an online tool to work with the data we were given, we get
So the best aproximation of r² is 0.861
We know the workers can unpack 48 books in 2 minutes, so how many minutes for 200?
Hey, I would be glad to help if i knew what the figure looked like ~