After selling one-third of its textbooks, a bookstore had 830 textbooks left. How many textbooks were in the bookstore initially?

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What is the ratio for the surface areas of the cones shown below, given that they are similar and that the ratio of their radil and altitudes is 4: 3? 23

Mariah is randomly choosing three books to read from the following: 5 mysteries, 7 biographies, and 8 science fiction novels. which of these statements are true? check all that apply. there are 20c3 possible ways to choose three books to read. there are 5c3 possible ways to choose three mysteries to read. there are 15c3 possible ways to choose three books that are not all mysteries. the probability that mariah will choose 3 mysteries can be expressed as . the probability that mariah will not choose all mysteries can be expressed as 1 −

Atotal of 505 tickets were sold for a school play they were either adult tickets or student tickets they were 55 more student tickets so than adult tickets how many adult tickets were sold ?