Tom has a bag of marbles: 4 red and 5
blue. He reaches in the bag and pulls out a
red. He DOES NOT replace the marble. He
reaches in again and pulls out another red
marble. What is the COMPOUND
probability that Tom will pull out a red and
a red? (Show your work calculating the
probability)

Fractions can be added and subtracted only if they're fractions. a. like b. proper c. improper d. unlike

One card is dealt from a 52 card deck. find the probability that the dealt card is a 4 or a black 7

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters