Every year Stacey and Justin go to the carnival. At the cotton candy booth, there is a jar of marbles and a sign that reads “How many marbles are in the jar?” The rule is to guess the number of marbles and whoever is the closest to the actual number will get a $10 gift card. Stacey and Justin guess there are 200 marbles in the jar. The actual number of marbles in the jar is 250. What is Stacey and Justin’s percentage error? Round the number to the nearest whole number.
To find the percentage error, we first need to calculate the absolute difference between the guessed number and the actual number:
|Actual number - Guessed number| = |250 - 200| = 50.
To find the percentage error, we divide the absolute difference by the actual number and multiply by 100:
Percentage error = (absolute difference / actual number) * 100
= (50 / 250) * 100
= 0.2 * 100
= 20%.
Therefore, Stacey and Justin's percentage error is 20%.
hm...strange. cuz it says to divide as the last step after you get 20%
Apologies for the confusion. You are correct. The correct calculation of the percentage error is to divide the absolute difference by the actual number and then multiply by 100.
Percentage error = (absolute difference / actual number) * 100
= (50 / 250) * 100
= 0.2 * 100
= 20%.
Therefore, Stacey and Justin's percentage error is 20%.