Andrew Geller

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List M (not shown) consists of 8 different integers, each of which is in the list shown. What is the standard deviation of the numbers in list M?

4, 6, 8, 10, 12, 14, 16, 18, 20, 22 List M (not shown) consists of 8 different integers, each of which is in the list shown. What is the standard deviation of the numbers in list M? (1) The average (arithmetic mean) of the numbers in list M is equal to the average of […]

List M (not shown) consists of 8 different integers, each of which is in the list shown. What is the standard deviation of the numbers in list M? Read the Full Article »

A department manager distributed a number of pens, pencils, and pads among the staff in the department, with each staff member receiving x pens, y pencils, and z pads. How many staff members were in the department?

A department manager distributed a number of pens, pencils, and pads among the staff in the department, with each staff member receiving x pens, y pencils, and z pads. How many staff members were in the department? (1) The numbers of pens, pencils, and pads that each staff member received were in the ratio 2:3:4,

A department manager distributed a number of pens, pencils, and pads among the staff in the department, with each staff member receiving x pens, y pencils, and z pads. How many staff members were in the department? Read the Full Article »

The average (arithmetic mean) of the integers from 200 to 400, inclusive, is how much greater than the average of the integers from 50 to 100, inclusive?

The average (arithmetic mean) of the integers from 200 to 400, inclusive, is how much greater than the average of the integers from 50 to 100, inclusive? (A) 150 (B) 175 (C) 200 (D) 225 (E) 300 Correct Answer: D Full explanation coming soon. Send us a note if you’d like this added to the

The average (arithmetic mean) of the integers from 200 to 400, inclusive, is how much greater than the average of the integers from 50 to 100, inclusive? Read the Full Article »