Question

The annual incomes of $1{,}000$ families range from $8200 to $98,000. In error, the largest income was entered on the computer as $980,000. The difference between the mean of the incorrect data and the mean of the actual data is

$882

$980

$1078

$482,000

$882,000

Answer: A

Concepts:mean

Difficulty rating: 1060

Solution:

Only one entry changed. The incorrect total exceeds the actual total by $\$980{,}000 - \$98{,}000 = \$882{,}000.$

Since this extra amount is spread over $1000$ families, the means differ by $\dfrac{\$882{,}000}{1000} = \$882.$

Thus, the correct answer is A .

1990 AMC 8 Problem 20

Answer: A

Solution:

Problem 20 in Other Years