Statistics & Probability

SAT PREP COURSE

DAY 4

MS. D’AGOSTINO

INCLUDED IN THIS SECTION… Data interpretation Statistics

Mean Median Mode Weighted Average Algebraic Average

Probability

Not included – Calculating the Standard Deviation

GRAPHS

Questions If the total expenses for Westin in 2014 were $10

million, how much money did people spend on the fire department and police department?

What day did Westin have highest high temperature? The lowest low temperature?

Between which two days did the high temperature show the greatest increase ? Greatest low temperature increase?

What day had the greatest difference in low and high temperature?

Mean Definition:

Example: If there are three children, aged 5, 6, and 13, what is the mean of their ages?

Median

Example: 200, 2, 667, 19, 4, 309, 44, 6, 1(Odd Number)

Example: 23, 27, 30, 40 (Even Number)

Mode

1, 5, 5, 7, 89, 4, 100, 276, 89, 4, 89, 1, 8

1, 5, 5, 7, 267, 4, 10004, 89, 4, 276, 1, 8

Weighted Average Fifteen members of the class had an average

SAT score of 500. Ten members of the same class had an average SAT score of 550. What is the average score of the entire class?

Algebraic Average What is the average of (3x +1) and (x – 3)?

Finding a Missing Number The average of a list of 10 numbers is 15. If

one of the numbers is removed the average of the remaining numbers is 14. What was the number that was removed?

Probability

Examples What is the probability of choosing an even

number at random from the set of:{6, 13, 5, 7, 2, 9}

From a normal deck of cards, What is the probability of picking a queen and a king?

Two Kings?

Two Hearts?

A heart or a 5?

Example On Monday Anderson High School’s basketball team

will play the team from Baker High School. On Wednesday Baker’s team will play the team from Cole High School. On Friday Cole will play Anderson. In each game either team has a 50% chance of winning.

What is the probability Anderson will win both games? What is the probability Baker will lose both games? What is the probability Anderson will win both games

and Baker will lose both games?

Geometric Probability The larger circle has a radius of 8 and

the small circle has a radius of 2. If a point is chosen at random from the large circle, what is probability that the point chosen will be in the small circle.

Permutation/Combination Permutation: Order Matters

President, Vice President, Secretary, Treasurer. Combination: Order Does Not Matter

Team, committee, group, club