Our library has 3,489 non-fiction books, 8,617 fiction books and 1,240 reference books. If there are 564 students and each student borrows 6 books, how many books will be left in the library?

What is the ratio for the surface areas of rectangle prisims shown below given that they are similar and that the ratio of their edge lengths is 7: 3

12 point are triangles pqr and stu congruent? what is the congruency that proves they are congruent? what is the perimeter of triangle pqr?

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?