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Sub 505 Level|   Statistics and Sets Problems|               
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carcass
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The average (arithmetic mean) of 6,8, and 10 equals the average 22 May 2017, 13:27
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C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

5% (low)

Question Stats:

94% (00:32) correct 6% (00:34) wrong based on 949 sessions

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The average (arithmetic mean) of 6,8, and 10 equals the average of 7,9 and

A) 5

B) 7

C) 8

D) 9

E) 11
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C
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The average (arithmetic mean) of 6,8, and 10 equals the average 22 May 2017, 18:59
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The average (arithmetic mean) of 6,8, and 10 equals the average of 7,9 and

A) 5

B) 7

C) 8

D) 9

E) 11
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Average of 6,8 and 10;
\(\frac{6 + 8 + 10}{3}\) = \(\frac{24}{3}\) = 8

Average of 7, 9 and x (let the unknown number be x) is equal to Average of 6,8 and 10.
\(\frac{7 + 9 + x}{3}\) = 8
16 + x = 24
x = 24 - 16 = 8
Answer C...

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The average (arithmetic mean) of 6,8, and 10 equals the average 12 Jun 2017, 11:47
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do they really ask this much easy question or it is just to boost morale ?
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Bunuel
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The average (arithmetic mean) of 6,8, and 10 equals the average 12 Jun 2017, 13:24
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srinidhi mishra
do they really ask this much easy question or it is just to boost morale ?
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This is an Official Question, which means that at some point in the past it was in the real pool of questions. So, yes you can get a question that easy on the exam.
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The average (arithmetic mean) of 6,8, and 10 equals the average 12 Jun 2017, 22:42
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6,8 and 10 are in arithmetic sequence, so mean is middle term = 8

If mean for 7,9 and x has to be 8, then x=8 fits easily as 7,8,9 will again be consecutive numbers, so middle term will be mean.
Answer C
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The average (arithmetic mean) of 6,8, and 10 equals the average 12 Jun 2017, 22:50
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If the average is the sum and the number of elements are the same,
the sum of the numbers must be the same
Let the unknown element be x

6+8+10 = 7+9+x
x=8(Option C)
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The average (arithmetic mean) of 6,8, and 10 equals the average 21 Apr 2020, 06:59
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6 + 8 + 10= 24/3= 8

(7 + 9+ x)/3 = 8

After solving x = 8

Answer is C.
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The average (arithmetic mean) of 6,8, and 10 equals the average 28 May 2023, 14:36
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Let's denote the missing number as x.

The average of 6, 8, and 10 is:

(6 + 8 + 10) / 3 = 24 / 3 = 8.

The average of 7, 9, and x should also be 8. So, we can set up the equation:

(7 + 9 + x) / 3 = 8.

Now, we solve for x:

7 + 9 + x = 8 * 3,
16 + x = 24,
x = 24 - 16,
x = 8.

Therefore, the missing number is 8.
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