# Probability

### Probability

This lesson answers the question: What are the differences between mean, median and mode in statistics? Also, we will learn how to calculate the probabilities out of a two-way frequency table, and figure out the trends.

#### Lessons

• Introduction
a)
Introduction to Probability
• What is probability?
• How to write probability as a fraction, decimal, and percent?
• How to draw a tree diagram?

b)
Introduction to statistics:
• What is mean?
• What is median?
• What is an outlier?
• What is mode?
• What is range?

c)
What is a two-way frequency table?

d)
How to read a two-way frequency table?

• 1.
The following is the money raised in a school fund raising activity by each class in grade 9: $1 000,$580, $810,$1 050, $840 and$600. What is the mean, median and mode amount of money raised by these six classes?

• 2.
Six hundred people were randomly selected in downtown. They were asked if they choose their clothes based on its comfort or style. The following is the results:
 Comfort Style Total Male 172 133 305 Female 115 180 295 Both 287 313 600
a)
What is the probability that a person in the survey is a female?

b)
What is the probability that a person chooses comfort over style?

c)
What is the probability that a male chooses style over comfort?

d)
Was there any assumption made in this survey?