epdf.pub_cbest-cliffs-test-prep13a9b242c7cb4125e6cca92d00a73d5a41681

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Arithmetic
Median
A median is simply the middle number of a list of numbers after it has been written
in order. (If the list contains an even number of items, average the two middle
numbers to get the median.) For example, in the following list — 3, 4, 6, 9, 21,
24, 56 — the number 9 is the median.
Mode
The mode is simply the number most frequently listed in a group of numbers. For
example, in the following list — 5, 9, 7, 3, 9, 4, 6, 9, 7, 9, 2 — the mode is 9 because
it appears more often than any other number.
Probability
Probability is the numerical measure of the chance of an outcome or event occurring.
When all outcomes are equally likely to occur, find the probability of the
occurrence of a given outcome by using the following formula:
probability =
number of favorable outcomes
number of possible outcomes
For example: Using the spinner shown below, what is the probability of spinning a
6 in one spin?
9
10
1
2
8
7
4
6
5
Because there is only one 6 on the spinner out of ten numbers and all the numbers
are equally spaced, the probability is 1 ⁄10.
What is the probability of tossing heads three consecutive times with a two-sided
fair coin?
Since each toss is independent and the odds are 1/2 for each toss, the probability is
1
⁄2 × 1 ⁄2 × 1 ⁄2 = 1 ⁄8
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