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How Addition Works

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Many people consider roulette to be an opportunity to win a lot of money very quickly. And yes it is possible and can be done with the right approaches, and in the right conditions. The appeal of quick money can lead to gambling addiction. Roulette, like all gambling, is a game of chance so , obviously, chance is involved. This does not mean that only chance is involved. If the roulette wheel is random then no one can predict with certainty that we will win or lose. That certainty belongs to astrology not maths. Addition Rule: If events A and B are mutually exclusive (disjoint), then. P(A or B) = P(A) + P(B) Otherwise, P(A or B) = P(A) + P(B) - P(A and B) Example 1: mutually exclusive: In a group of 101 students 30 are freshmen and 41 are sophomores. Find the probability that a student picked from this group at random is either a freshman or sophomore.



Parents:  You can easily do these exercises away from the computer anytime!

Make sets of fish crackers at snack time...  Use marbles, rocks or anything else around the house for practice.  Just be sure that the set pieces (in both sets) are all the same, so it doesn't cause confusion.  For example, don't have one set be rocks and the other be marbles... Skittles and M&M's work too, but I'd save these for a special math reward.

Remember how to set it up and do it:

  • Make two sets of the same kind of object
  • Count how many are in each set
  • Write out the problem (like 2+3=) << optional step
  • Put the sets together
  • Count how many are in the final set
  • Write down the answer << optional step

It's a good idea to keep the numbers small when working with sets...  Just use 1-10 for each set.

The goal is to get the basic idea of adding two sets together.  (You can even do three or more sets when your child really gets good at it!)