The area of a square is 100 square centimeters. What is its perimeter?
A. 40 centimeters
B. 50 centimeters
C. 80 centimeters
D. 100 centimeters
E. 400 centimeters

An advertising firm has an old computer that can prepare a whole mailing in 6 hours. with the of newer model the job is complete in 2 hours. how long would it take the newer model to do the job alone?

What is the sum of these mixed numbers 2 1/8 + 4 3/8

Aclass consists of 55% boys and 45% girls. it is observed that 25% of the class are boys and scored an a on the test, and 35% of the class are girls and scored an a on the test. if a student is chosen at random and is found to be a girl, the probability that the student scored an ais