What is the average (arithmetic mean) of w, x, y, z, and 10?
(1) The average (arithmetic mean) of w and y is 7.5; the average (arithmetic mean) of x and z is 2.5
(2) -(-z - y -x - w) = 20
The OA is the option D.
How can I use statement (1) to get an answer here? Experts, may you help me? I'd be thankful.
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What is the average (arithmetic mean) of w, x, y, z, and 10?
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mbawisdom
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We want to find out what (w + x + y + z + 10)/5 equals.M7MBA wrote:What is the average (arithmetic mean) of w, x, y, z, and 10?
(1) The average (arithmetic mean) of w and y is 7.5; the average (arithmetic mean) of x and z is 2.5
(2) -(-z - y -x - w) = 20
The OA is the option D.
How can I use statement (1) to get an answer here? Experts, may you help me? I'd be thankful.
(1) tells us that (w + y)/2 = 7.5 or that w + y = 15, it also tells us that (x + z)/2 = 2.5 or that x + z = 5
Thus, we can use this to put into equation
(w + x + y + z + 10)/5
((x + z) + (w + y) + 10)/5
(5 + 15 + 10)/5
30/5
6
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Jay@ManhattanReview
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We have to get the average (arithmetic mean) of w, x, y, z, and 10.M7MBA wrote:What is the average (arithmetic mean) of w, x, y, z, and 10?
(1) The average (arithmetic mean) of w and y is 7.5; the average (arithmetic mean) of x and z is 2.5
(2) -(-z - y -x - w) = 20
The OA is the option D.
How can I use statement (1) to get an answer here? Experts, may you help me? I'd be thankful.
The average (arithmetic mean) of w, x, y, z, and 10 = (w + x + y + x + 10)/5.
If we get the value of (w + x + y + x), we get the answer.
Let's take each statement one by one.
(1) The average (arithmetic mean) of w and y is 7.5; the average (arithmetic mean) of x and z is 2.5.
=> (w + y)/2 = 7.5 => w + y = 15
=> (x + z)/2 = 2.5 => x + z = 5
=> w + x + y + x = 15 + 5 = 20. Unique answer. Sufficient.
(2) -(-z - y -x - w) = 20
=> z + y +x + w = 20. Unique answer. Sufficient.
The correct answer: D
Hope this helps!
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