In the arithmetic sequence t1, t2, t3, . . . , tn.  t1 = 23 and t_n = t_{n - 1} - 3 for each n >1. What is the value of n when tn = -4 ?

If a certain sample of data has a mean of 20.0 and astandard deviation of 3.0, which of the following values is more than 2.5 standard deviations from the mean?

If the average (arithmeticmean) of the 4 numbers n + 2, 2n - 3, 4n + 1, and 7n + 4 is 15, what is thevalue of n ?

If xy + z = x(y + z), whichof the following must be true?

At a constant rate of flow,it takes 20 minutes to fill a swimming pool if a large hose is used and 30minutes if a small hose is used. Atthese constant rates, how many minutes will it take to fill the pool when bothhoses are used simultaneously?

If x is a negative integer,which of the following expressions has the LEAST value?

If ~$\frac{x}{y}=\frac{2}{3}$~, then ~$\frac{x-y}{x}$~ =

According to the directionson a can of frozen orange juice concentrate, 1 can of concentrate is to bemixed with 3 cans of water to make orange juice. How many 12-ounce cans of the concentrate arerequired to prepare 200 6-ounce servings of orange juice?

A company plans to assign identification numbers to its employees. Each number is to consist of four different digits from 0 to 9, inclusive, except that the first digit cannot be 0. How many different identification numbers are possible?

A circular jogging track formsthe edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at theaverage rate of 3 miles per hour. If trepresents the number of hours it took Johanna to walk completely around thelake, which of the following is a correct statement?