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Introduction to Counting & ProbabilityFundamentals of counting and probability, including casework, multiplication, permutations, combinations, Pascal's triangle, probability, combinatorial identities, and the Binomial Theorem. 
12 weeks 
12 weeks ARE YOU READY? DO YOU NEED THIS? SYLLABUS 
Schedule
Tuesday
Jan 5  Mar 23 
7:30  9:00
PM ET
Jan 5  Mar 23
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Alyssa Zisk 
$355
$400 w/books

$355
CLOSED
With Books $400

Friday
Jan 15  Apr 2 
7:30  9:00
PM ET
Jan 15  Apr 2
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Luís Finotti 
$355
$400 w/books

$355
WAITLIST
With Books $400

Sunday
Jan 31  Apr 18 
7:30  9:00
PM ET
Jan 31  Apr 18
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Emily Castner 
$355
$400 w/books

$355
ENROLL
With Books $400

Monday
Feb 8  Apr 26 
7:30  9:00
PM ET
Feb 8  Apr 26
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
sarahmarie belcastro 
$355
$400 w/books

$355
ENROLL
With Books $400

Thursday
Feb 11  Apr 29 
7:30  9:00
PM ET
Feb 11  Apr 29
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Chuck Garner 
$355
$400 w/books

$355
ENROLL
With Books $400

Friday
Mar 5  May 21 
7:30  9:00
PM ET
Mar 5  May 21
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Ekaterina Machavariani 
$355
$400 w/books

$355
ENROLL
With Books $400

Wednesday
Mar 17  Jun 2 
7:30  9:00
PM ET
Mar 17  Jun 2
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Joshua Zucker 
$355
$400 w/books

$355
ENROLL
With Books $400

Sunday
Mar 21  Jun 13 
7:30  9:00
PM ET
Mar 21  Jun 13
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Jason Gorgia 
$355
$400 w/books

$355
ENROLL
With Books $400

Monday
Apr 19  Jul 19 
7:30  9:00
PM ET
Apr 19  Jul 19
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Carl Yerger 
$355
$400 w/books

$355
ENROLL
With Books $400

Friday
Apr 30  Jul 16 
7:30  9:00
PM ET
Apr 30  Jul 16
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Dan Kneezel 
$355
$400 w/books

$355
ENROLL
With Books $400

Summer 2021  This course will be offered in Summer 2021. Click here to join our mailing list to be notified when the course schedule is available. 
AoPS Holidays
There are no classes May 29–31, July 3–5, and September 4–6.
Who Should Take?
This course is appropriate for students in grades 69 who have mastered basic algebra up through solving linear equations and manipulating multivariable expressions. Students who have completed our Introduction to Algebra A course should have sufficient background. This course is roughly the same difficulty as our Introduction to Number Theory class. For those preparing for contests, this course should help with MATHCOUNTS and the AMC 8/10/12 tests.Lessons
Lesson 1  Lists, Venn Diagrams, Addition, Multiplication 
Lesson 2  Casework, Constructions, and Restriction 
Lesson 3  Overcounting and Combinations 
Lesson 4  Combinations and Distinguishability 
Lesson 5  Challenging Problems Day 
Lesson 6  Introduction to Probability 
Lesson 7  Probability and Arithmetic 
Lesson 8  Geometric Probability, Think About It!, and Expected Value 
Lesson 9  Pascal's Triangle and Identities 
Lesson 10  The Hockey Stick Identity 
Lesson 11  The Binomial Theorem 
Lesson 12  Challenging Problems Day 2 
Required Textbook
Introduction to Counting & Probability
A thorough introduction for students in grades 710 to counting and probability topics such as permutations, combinations, Pascal's triangle, geometric probability, basic combinatorial identities, the Binomial Theorem, and more.
