DISCRETE PROBABILITY  (Chs14, 15,16)

Here is an excellent video which gives questions about Tree Diagrams. Pause the video and try to solve it before you watch the rest.
Here is an excellent Binomial probability distribution problem.  Solve the problem and then go to the links below for the videos which explain the solution.
LINKS FOR SOLUTION
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=706&solution=3.1
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=706&solution=3.2
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=706&solution=3.3
Here is an excellent Question which goes through the fundamental concepts relating to VENN DIAGRAMS and whether events are INDEPENDENT or not.
Try the question first and then go to the links below for the solution.
LINKS FOR SOLUTION
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=609&solution=6.1
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=609&solution=6.2
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=609&solution=6.3
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=609&solution=6.4
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=609&solution=6.5

Here is another good practice question on VENN DIAGRAMS
LINKS FOR SOLUTION
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=601&solution=4.1
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=601&solution=4.2
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=601&solution=4.3
Here is another good question on TREE DIAGRAMS
LINKS FOR SOLUTION
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=600&solution=2.1
http://www.examsolutions.net/a-level-maths-papers/worked-solution/worked-solution.php?paper_id=600&solution=2.2

Here is a really good video which goes through Binomial Distribution questions and explains all the basic concepts really well. 
Pause the video and solve each problem yourself before you watch the solution.