The coefficient of determination represents the percentage of the data that is the closest to the line of best fit.
the total variation in y can be explained by the linear relationship between x and y
550-500 is not 500 it’s 50
You can group first two conjunctions and second two:
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In first brackets you have common
and in second brackets common is 5:
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The two numbers are very near 7200 and 300. The sum of those is a good estimate of your sum:
... 7200 + 300 = 7500
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If you're taught methods of addition that include "make a ten" or "make a hundred", you know you can "borrow" a 1 from 7203 (making it 7202) and loan that 1 to 299 to make it 300. Now, you know your sum is exactly 7202+300 = 7502, with no estimation necessary.
