math
posted by Anonymous .
your school librarian has asked your class for some help on the purchase of some new bookcases with two shelves each. She has 300 new books she needs to shelve. One half of the books are half an inch thick. Ones third of them are one fourth of an inch thick, and the rest are three fourths of an inch thick. Her shelves are 30 inches long. How many bookcases should she buy? Show your work

150*1/2 + 100*1/4 + 50*3/4 = 276"
She needs 9+ shelves, or 5 bookcases