Cthulhu thinks its goat friends are looking a little thin, so it sponsors a weight gain program. Goats are weighed at the start and end of a week. The more weight gained, the better!
You can download the start workbook. It looks like this:
Write a program that computes the average start and end weights, and the average gain. Only include valid data. The names are all OK, so you don't need to check them. However, as you can see, there's some bad numeric data. Exclude it from the analysis. Also exclude negative weights. No floating goats!
Here's what the output should look like:
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