(3) probability

Question 1

-What does it mean if two events are independent and what is the proof for this?

Answer 1

• Independent it means the outcome of one event does not affect whether the other event occurs.
• P(A) x P(B) = P(AnB)

Question 2

what does n(a) mean?

Answer 2

-The number of outcomes in each event.

Question 3

if A and B are independent what does it mean if P(A|B)

Answer 3

• P(A|B) = P(A)

Question 4

what is the formula for P(A|B)

Answer 4

P(AnB) / P(B)

The probability of the intersection over the term on the right.

Question 5

What is the formula for P(AuB)

Answer 5

P(A) + P(B) - P(AnB)

Question 6

What does it mean if two events are mutually exclusive?

Answer 6

-P(AnB) = 0 and the closed curves do not overlap.

Question 7

What is a way of denoting an empty set?

Answer 7

o with a cross through it.

Question 8

What is the first step for a probability tree diagram?

Answer 8

-See if it is replaced or not replaced.

Question 9

What is a two way table for a and b?

Answer 9

-a and a’ in one and B and B’ in another.

Question 10

What is the strategy for finding the right area when shading?

Answer 10

• Shade everything it is asking
• Then use double shaded for n
• Use single shaded for u

Question 11

What does it mean if a Venn diagram is inside a Venn diagram?

Answer 11

-it means it is a subset and they happen together

Question 12

What is the first step when being asked to construct a Venn diagram?

Answer 12

-Start from the middle then work your way out.

Question 13

What is the strategy if a question is on a day 80 students bring a lunchbox, given that all contain sandwiches and a drink work out something else?

Answer 13

-Use the notation and form a fraction.