In this module, you'll learn all of the concepts, techniques and strategies needed to answer probability questions on the GMAT. In particular, this module covers:

 Finding probabilities by counting Complements “At least” & “at most” questions “Or” probabilities “And” probabilities Mutually exclusive events Independent events

### Two ways to prepare

Beneath each video lesson in this module, we have a Related Resource box with practice questions that test the concepts covered in the video. With this lesson format, you have two learning options:

• Watch the video lesson first and then reinforce your learning by answering several related questions, or…
• Tackle the practice questions first and watch the lesson only if you need help with the concepts the practice questions test

## GMAT PROBABILITY VIDEOS

• 1. Lesson: Introduction to Probability (6:42)
• 2. Question: Sum of 11 (2:35)
• 3. Lesson: The Complement (6:06)
• 4. Question: At Least 1 Even Number (3:39)
• 5. Lesson: Mutually Exclusive Events (3:21)
• 6. Lesson: Probability of Event A OR Event B (4:54)
• 7. Lesson: Applying the OR Rule (2:17)
• 8. Question: Red or Green Ball (3:06)
• 9. Lesson: Probability of Event A AND Event B (3:16)
• 10. Question: 2nd Ball is Yellow (2:35)
• 11. Lesson: Independent Events (6:25)
• 12. Lesson: Determining Independence (3:52)
• 13. Lesson: Rewriting Questions (5:33)
• 14. Question: Total Number of Balls (2:47)
• 15. Lesson: Listing vs Counting vs Probability Rules (7:40)
• 16. Lesson: General GMAT Probability Strategies (2:03)
• 17. Lesson: Guessing Strategies (5:31)
• 18. Question: Green Ball (2:24)
• 19. Question: Target (2:04)
• 20. Question: Yellow Ball or Red Ball (2:13)
• 21. Question: Same Color (3:02)
• 22. Question: 2 heads (4:02)
• 23. Question: Socks (4:40)
Total viewing time for the GMAT Probability module: 91 minutes.

Problem Solving (level of difficulty: 350 to 500)

Sum of 9

Most likely interval

Sets M and T

5 coin flips

10 envelopes

Problem Solving (level of difficulty: 500 to 650)

120 marbles

Rosebushes

Six coin flips

Dice game

Juniors and seniors

Three coin tosses

4 fair dice

Problem Solving (level of difficulty: 650 to 800)

2 girls and 2 boys

Random bouquet

Four expressions

Andrew and Karen

Matching socks

Littermates

Data Sufficiency (level of difficulty: 650 to 800)

Leila at carnival

Selecting representatives

Red ball vs white ball

White or even number

## Practice from the Official Guide

Official Guide for GMAT Review (2017 edition)

Problem Solving: 8, 21, 22, 27, 31, 33, 45, 46, 49, 57, 59, 63, 66, 67, 70, 74, 76, 78, 84, 92, 93, 94, 104, 110, 121, 137, 143, 152, 163, 170, 171, 172, 175, 183, 187, 188, 191, 211, 217, 222, 224, 227, 229, 230

Data Sufficiency: 235, 245, 246, 247, 261, 268, 271, 272, 273, 278, 279, 288, 292, 293, 301, 305, 307, 316, 335, 338, 345, 349, 352, 355, 357, 374, 379, 384, 398, 399, 401, 404

Official Guide for GMAT Review (2016 edition)

Problem Solving: 8, 80, 129, 136, 202, 219

Data Sufficiency: 7, 50, 140

Official Guide for GMAT Review (2015/13th edition)

Problem Solving: 10, 68, 107, 173, 193, 215

Data Sufficiency: 3, 39, 125

While answering practice questions from the Official Guide for GMAT Review (2017, 2016 or 2015), you can enter your responses directly into our downloadable Improvement Chart. This will help track your progress and identify areas of weakness.