39. If the letters A, B, C, D, E, F represent the numbers 4 to 9 in some order, and
A + C = D
A + D = 2B
C + E = 2F
then what number does F represent?

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?

If you are just building your payment history, how many points from a perfect score will you possibly miss?

Given a: b and b: c, find a: b: c. write the ratio in simplest form. a: b=6: 10 and b: c=21: 33