## How do you find the probability of an individual?

**Divide the number of events by the number of possible outcomes.**

- Determine a single event with a single outcome. …
- Identify the total number of outcomes that can occur. …
- Divide the number of events by the number of possible outcomes.

## How do you find the probability of one or another?

If two events have no outcomes in common, the probability that one or the other occurs is **the sum of their individual probabilities**. The probability that an event does not occur is 1 minus the probability that the event does occur.

## How do we determine if an individual is unusual?

Unusual values are **values that are more than 2 standard deviations away from the µ – mean**. The 68-95-99.7 rule apples only to data values that are 1,2, or 3 standard deviations from the mean. We can generalize this rule if we know precisely how many standard deviations from the mean (µ) a particular value lies.

## How do you find the probability of random selection?

**P (X) = n/N**; where ‘n’ is the number of the favourable outcomes and ‘N’ is the number of total possible outcomes.

## How do you find the probability of independent events?

Events A and B are independent if the equation **P(A∩B) = P(A) · P(B)** holds true. You can use the equation to check if events are independent; multiply the probabilities of the two events together to see if they equal the probability of them both happening together.

## How do you find the probability of a group of people?

Quote from video: *Our female chart we have seven out of fourteen. If we add these two probabilities together nine. And seven we get 16 out of 14.*

## How do you find the probability of either A or B?

Inclusion-Exclusion Rule: The probability of either A or B (or both) occurring is **P(A U B) = P(A) + P(B) – P(AB)**. Conditional Probability: The probability that A occurs given that B has occurred = P(A|B). In other words, among those cases where B has occurred, P(A|B) is the proportion of cases in which event A occurs.

## How do you find the probability of both A and B?

Formula for the probability of A and B (independent events): **p(A and B)** **= p(A) * p(B)**. If the probability of one event doesn’t affect the other, you have an independent event. All you do is multiply the probability of one by the probability of another.