At a garage sale, all of the prices of the items sold were different.  If the price of a radio sold at the garage sale was both the 15th highest price and the 20th lowest price among the prices of the items sold, how many items were sold at the garage sale?

On line segment AD shown, AB = ~$\frac{1}{2}$~CD and BC = 10.  If AD = 100, then CD =

If   ~$\sqrt{x}=25$~ , then x³ – x² =

Which of the following is equal to 2^k5^{k − 1} ?

The number of defects in the first five cars to come through a new production line are 9, 7, 10, 4, and 6, respectively.  If the sixth car through the production line has either 3, 7, or 12 defects, for which of theses values does the mean number of defects per car for the first six cars equal the median?

I. 3
II. 7
III. 12

99,999² - 1² =

Company S produces two kinds of stereos:  basic and deluxe.  Of the stereos produced by Company S last month, ~$\frac{2}{3}$~  were basic and the rest were deluxe.  If it takes ~$\frac{7}{5}$~  as many hours to produce a deluxe stereo as it does to produce a basic stereo, then the number of hours it took to produce the deluxe stereos last month was what fraction of the total number of hours it took to produce all the stereos?

If an integer n is to be chosen at random from the integers 1 to 96, inclusive, what is the probability that n(n + 1)(n + 2) will be divisible by 8?

For the cube shown above, what is the degree measure of  ~$\angle PQR$~?

If a code word is defined to be a sequence of different letters chosen from the 10 letters A, B, C, D, E, F, G, H, I, and J, what is the ratio of the number of 5-letter code words to the number of 4-letter code words?