**PROBABILITY and COUNTING METHODS**

**Here are some videos below which deal with key concepts in this topic.**

This video revises the key concept of Probability Tree Diagrams and how to use them. This video goes through the Combinations (selections) formula and solving worded problems. |
This video goes over Permuations (arrangements) and explains where the formula for nPr comes from. This video clearly explains the fundamental counting principle of the difference between AND (multiply) and OR (add) |
This video gives a few examples of using the Permutation formula and solving worded problemsThis excellent video explains how to solve arrangement problems similar to in the textbook when there can be restrictions. |

This excellent video explains the difference between arrangements (permutations) and selections (combinations) with examples. |
This video explains how to do questions similar to the textbook where committees are selected with different restrictons |
This video goes step by step through a Venn Diagram worded problem and clearly shows you how to interpret it. |

Here is another video which gives you practice solving Venn Diagram problems.Here is a video about shading the regions in a Venn Diagram. Excellent revison! |
Here is another question that you can practise on worded problems and Venn DiagramsThis video explains why you shouldn't go into Tattslotto! It explains the probability of winning the Mega Jackpot in the US (similar to Powerball in Australia) |
This video revises Probability Tree Diagrams when selecting objects WITHOUT replacement |

## Here are some videos based directly on problems from our textbook by an Australian maths teacher.

Here is a question by a teacher based on Ex 12 C Q6 from our textbook!! He explains combinations and probability. |
Here, this teacher has solved questions 2,3,4, 7. 8, 11 from Ex 12D. A great resource if you get stuck on any of these problems! |
Here he has solved Ex 12D Q9 in detail |

In this video, he explains the difference between Permuations and Combinations. Goes through Ex 12 DQ9 |
Here he goes through Karnaugh Maps. Excellent revision! |
This video goes through the vocabulary and basic concepts of Probability (the first three exercises of Ch 10) |

__PRACTICE QUESTIONS__**Try these practice questions. Watch the solutions in the video link when done, or click on the next page of the document to see it.**

**PRACTICE QUESTIONS ON PERMUTATIONS and COMBINATIONS**

**PRACTICE QUESTIONS ON PROBABILITY**