Or - Event A or event B

CONCEPTS

Equation

• Probability 1 Event Occurs =

Number of desired events / Total number of possible events +

Number of desired events / Total number of possible events

Tips

• Always look for the word "or“, or the phrase "what is the probability of x happening“.

PRACTICE PROBLEMS

Question 1 What is probability a red or green ball is selected?

-- Answer -- 5/9

2/9 + 3/9 = 5/9

“Or” appears in the question. Use a “+”

ACT PRACTICE PROBLEMS

1/1