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Can (3,5 and square root 34) be sides on a right triangle?

On saturday a souvenir shop had 125 customers. sixty four percent of the costumers paid with a credit card. how many costumers paid with cash?

The probability that a student graduating from suburban state university has student loans to pay off after graduation is .60. if two students are randomly selected from this university, what is the probability that neither of them has student loans to pay off after graduation?