SOLUTION: A card is drawn from a well-shuffled deck of 52 cards. What is the probability of drawing a diamond or a 7. Please solve, and I did not do well on this question. Thank you.

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Question 977014: A card is drawn from a well-shuffled deck of 52 cards. What is the probability of drawing a diamond or a 7. Please solve, and I did not do well on this question. Thank you.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Imagine the deck cards arranged organized from A to K in one direction and each suit orthogally to the A to K arrangement. You can make a count of all the cards which are 7 or diamonds. The deck has FOUR 7's, THIRTEEN diamonds, and this is 4%2B13-1. The reason for MINUS ONE is that one of the cards is both a 7 and a diamond; so this is subtracted in order to not count it twice.

Sixteen cards of the deck are 7's or diamonds.

NOW shuffle the 52-card deck. Shuffle it well.

Chance of pulling 7 or diamond is 16%2F52.
This is 4%2F13=0.3077...