Dave has 500 baseball cards, which is as many cards as Eric and Travis have combined. Eric has three times as many cards as Travis. If Travis is donated x cards, Eric 3x cards, and Dave 500 cards. What is the total number of calls that all of them have? Also, explain how we figure out the amount of cards Travis has and the amount Eric has

Astandard deck of cards contains 52 cards. one card is selected from the deck. (a) compute the probability of randomly selecting a diamond or heart. (type an integer or a decimal rounded to three decimal places as needed.) (b) compute the probability of randomly selecting a diamond or heart or club. (type an integer or a decimal rounded to three decimal places as needed.) (c) compute the probability of randomly selecting queen or club. (type an integer or a decimal rounded to three decimal places as needed.)