Question

The manager at Food Town estimates that the store sold 325 jars of spaghetti sauce last week. The store actually sold 297 jars of spaghetti sauce. What is the manager’s percent error?

Answer 1

Answer: 9.43%

Step-by-step explanation:

The formula to calculate the percent error is given by :-

$\% \text{ error}=\dfrac{|\text{Estimated value - Actual value}|}{\text{Actual value}}}\times100$

Given : The manager at Food Town estimates that the store sold 325 jars of spaghetti sauce last week. The store actually sold 297 jars of spaghetti sauce.

i.e.  Estimated value = 325

Actual value = 297

Then , the percentage error would be :-

$\% \text{ error}=\dfrac{|325-297|}{297}\times100\\\\=\dfrac{|28|}{297}\times100\\\\=\dfrac{28}{297}\times100=9.42760942761\approx9.43\%$

hence, the manager’s percent error is approximately 9.43% .

Answer 2

There is a positive, linear relationship between the correct and guessed calories. The guessed  calories for 5 oz. of spaghetti with tomato sauce and the cream-filled snack cake are unusually  high and do not appear to fit the overall pattern displayed for the other foods.  The correlation is r = 0.825 . This agrees with the positive association observed in the plot; it is not closer to 1  because of the unusual guessed calories for spaghetti and cake.  The fact that the guesses are  all higher than the true calorie count does not influence the correlation. The correlation r would  not change if every guess were 100 calories higher. The correlation r does not change if a  constant is added to all values of a variable because the standardized values would be unchanged.  The correlation without these two foods is r = 0.984 . The correlation is closer to 1 because  the relationship is much stronger without these two foods.