Question

Becca scored 10, 10, 15, 15, 18, 20, 20, and 20 points in her first 8 basketball games of the season. By how much will her mean score improve if she scores 25 points in her 9th game? Explain.

Answer 1

Her mean score increased by 3.125 or 3 1/8 (just use whatever your teacher wants)

Explanation:

Let's calculate the mean of Becca's first eight:

Mean = sum of items/# of items
(10 + 10 + 15 + 15 + 18 + 20 + 20 + 20)/8 = 16

Now let's see the mean when she scores 25 (add this to the top) in her 9th game (new # of items)

(10 + 10 + 15 + 15 + 18 + 20 + 20 + 20 + 25)/8 = 19 1/8 or 19.125

Improvement is new mean - old mean, so 19 1/8 - 16 = 3 1/8 or 3.125