A library buys 36 English books, 48 Science books and 72 Mathematics books. The thickness of each book is the same. Now, the librarian wants the books to be placed in stacks, such that each stack has books of the same subject, and the height of each stack is the same. Also, the librarian wants as few stacks as possible. How many stacks of books will there be?

2x - 20 = 32 20 - 3x = 8 6x - 8 = 16 -13 - 3x = -10

Agreeting card company can produce a box of cards for $7.50. if the initial investment by the company was $50,000, how many boxes of cards must be produced before the average cost per box falls to $10.50?

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?