Caluclate the Mean Absolute Deviation for the following data:
9, 10, 11, 11, 12, 12, 13, 13, 14, and 15.

A) 2.3

B) 1.4

C) 1.6

D) 3.8

Find the standard deviation and variance for the following data: 10, 12, 8, 14, and 16.

A) \$sqrt 13\$

B) \$sqrt 16\$

C) \$sqrt 8\$

D) \$sqrt 5\$

A population of a small town increased from 1,500 to 1,800 over a year. What is the percentage increase in the population?

A) 28%

B) 25%

C) 22%

D) 20%

Students in an online course rate the difficulty level (out of 10) for each week’s material: 7, 9, 8, 6, 10, 8, 7, and 5. Calculate the Mean Absolute Deviation(MAD).

A) 1.25

B) 2.36

C) 3.45

D) 4.56

A company produces batteries, and the lifetimes (in hours) of a sample of 10 batteries are recorded as follows: 200, 210, 190, 205, 195, 215, 220, 225, 190, and 200. Calculate the standard deviation of the lifetimes of these batteries.

A) 11.62 hours

B) 10.32 hours

C) 12.07 hours

D) 10.89 hours

A company’s revenue decreased from $2,000,000 to $1,500,000. What is the percentage decrease?

A) 25%

B) 27%

C) 30%

D) 35%

The following data set represents the number of hours studied by 10 students in a week: 5, 7, x, 4, 6, 9, 7, 5, 8, and 6 if mean is 6.5 and MAD is 1.35. Find the value of x?

A) 8

B) 10

C) 15

D) 19

Calculate the value of x and standard deviation of the following data set: 12, 34, 44, 64, 55, 75, x, and 99.

A) x = 50, sd = 25.68

B) x = 50, sd = 24.59

C) x = 55, sd = 32.58

D) x = 59, sd = 24.59

A company’s revenue last year was $500,000. This year, the company’s revenue increased by 20% in the first half of the year compared to the same period last year, but then decreased by 10% in the second half of the year compared to the same period last year. What is the company’s total revenue for this year?

A) $465,000

B) $535,000

C) $1,050,000

D) $52,500

The mean and variance of 5 observations are 5 and 8 respectively. If 3 observations are 1, 3, 5, then the sum of cubes of the remaining two observations is

A) 1702

B) 1125

C) 1082

D) 2992