113 Math
113.038.01 Probability - Addition rule of probability

Addition rule of probability

Say you have a deck of 52 cards. What is the probability of getting a random card that is hearts OR a Jack?
- There are 13/52 hearts
- There are 4/52
- The probability is 13/52 + 4/52 - 1/52, or the probability of hearts plus the probability of Jacks, minus the probability of Hearts AND Jack.

Think of it like an overlapping Venn diagram and you're adding the area of the two circles, then subtracting the area of the overlapping part.

  • statistics
  • probabilities