ACT Math: Pre-Algebra: Drill 6, Problem 2. What score must be earned to bring Jenny's overall mean to at least 87?
|Foreign Language||Arabic Subtitled|
|Pre-Algebra||Simple descriptive statistics (mean, median, mode, range)|
Understanding simple descriptive statistics
|Product Type||ACT Math|
|Statistics||Mean, Median, and Mode|
And here are the potential answers...
OK so what is this question asking?
Well it's really the advanced ninja version of taking averages.
Poor Jenny took 4 tests and she's going to take another
-- she will have taken 5 tests in total.
And the TOTAL of these 5 tests must have an average of 87 -- or in other words, they
must total to 5 times 87 or have a total of 435.
So the answer comes from just adding up the previous 4 tests, subtracting that number
from 435 and whatever is left is what she has to get to average an 87.
So if we add the previous 4 tests we get a sub-total of 345.
Subtract 345 from 435 and we get 90.
So she has to get a 90 or better on the last test.
As in, "Deadly weapons."