The mean of four numbers is 70. The mean increases to 80 when a fifth number is added. What is the fifth number?

The law of cosines can only be applied to right triangles. True or False.

The price of a computer component is decreasing at a rate of 12% per year. State whether this decrease is linear or exponential. if the component costs $90 today, what will it cost in three years?

For which of the following angles is cosecant undefined? 45° 60° 180° 270°

On a farm, 4 1/2 out of every 15 acres of land are used to grow crops.

Use the explicit formula an = a1 + (n - 1) • d to find the 250th term of the sequence below. 57, 66, 75, 84, 93, ... A. 2334 B. 2307 C. 2241 D. 2298

Suppose that textbook weights are normally distributed. You measure 28 textbooks' weights, and find they have a mean weight of 76 ounces. Assume the population standard deviation is 12.3 ounces.

ABC Bookstore rents a storage space that is 75 ft x 50 ft and 15 ft high. It is charged $2.50 per square foot. How much does ABC Bookstore spend on storage space? O A. $140,625 O B. $9375 O C. $2500 O D. $3750

31/9 as a mixed number

Find 4x when 3x equals 3

Solve 64x3 - 1 = 0.