Victoria selects a card at random from a box of blank greeting cards. The box has 5 "Happy Birthday" cards, 11 "Thank You" cards, and 4 "Get Well Soon" cards. What is the probability that she selects a "Happy Birthday" or "Get Well Soon" card?

Question

anonymous · Answer

Victoria is in an awfully interesting situation, if those cards are meant for her.

anonymous · Answer

Ah they are blank.

anonymous · Answer

5 happy birthdays, plus 4 get well soons, out of 20 cards= 9/20

anonymous · Answer

So how many happy birthday cards are there?
How many get well soon types?

The probability of getting a particular kind of card is :
$$\frac{\text{number of that kind}}{\text{total of all cards in the box}}$$

And the probability of one event OR another is the probability of the first event plus the probability of the second.

anonymous · Answer

45%