GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 23 Sep 2018, 05:38

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# The average (arithmetic mean) weight of two men is x, which is twice

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 49320
The average (arithmetic mean) weight of two men is x, which is twice  [#permalink]

### Show Tags

08 Jan 2018, 07:25
00:00

Difficulty:

45% (medium)

Question Stats:

53% (01:21) correct 47% (01:25) wrong based on 43 sessions

### HideShow timer Statistics

The average (arithmetic mean) weight of two men is x, which is twice the average weight of three different men. Which of the following expresses the average weight of all five men in terms of x?

A. x/2
B. 3x/5
C. 7x/2
D. 7x/10
E. 8x/5

_________________
DS Forum Moderator
Joined: 22 Aug 2013
Posts: 1343
Location: India
Re: The average (arithmetic mean) weight of two men is x, which is twice  [#permalink]

### Show Tags

08 Jan 2018, 11:04
Bunuel wrote:
The average (arithmetic mean) weight of two men is x, which is twice the average weight of three different men. Which of the following expresses the average weight of all five men in terms of x?

A. x/2
B. 3x/5
C. 7x/2
D. 7x/10
E. 8x/5

Since average weight of first two men is 'x', their total weight = 2x.

Also 'x' is twice the average weight of last three men. That means average weight of last three men = x/2, thus total weight of last three men = 3x/2.

So, total weight of these five men = 2x + 3x/2 = 7x/2. And so their average weight = (7x/2) / 5 = 7x/10.

Hence D answer
Senior SC Moderator
Joined: 22 May 2016
Posts: 1979
The average (arithmetic mean) weight of two men is x, which is twice  [#permalink]

### Show Tags

08 Jan 2018, 15:31
Bunuel wrote:
The average (arithmetic mean) weight of two men is x, which is twice the average weight of three different men. Which of the following expresses the average weight of all five men in terms of x?

A. x/2
B. 3x/5
C. 7x/2
D. 7x/10
E. 8x/5

Another approach: smart numbers. Have the men in each group (2 men, 3 men) weigh the same. Then each man's weight is also his group's average weight.

The men are A, B, C, D, and E

Let A and B each weigh 10.
10 = x
($$\frac{10+10}{2}=10$$)

x = 10 is twice the average of the other three men. Their average is 5.
Let C, D, and E each weigh 5.
($$\frac{5+5+5}{3}=5$$)

Average of all five men?
$$\frac{SumOfWeights}{NumberOfMen} = \frac{10+10+5+5+5}{5} = 7$$ average

With x = 10, find the answer that yields 7.

A. x/2 = 5 NO
B. 3x/5 = 6 NO
C. 7x/2 = 35 NO
D. 7x/10 = 7 YES
E. 8x/5 = 16 NO

Answer D
_________________

In the depths of winter, I finally learned
that within me there lay an invincible summer.

-- Albert Camus, "Return to Tipasa"

The average (arithmetic mean) weight of two men is x, which is twice &nbs [#permalink] 08 Jan 2018, 15:31
Display posts from previous: Sort by

# The average (arithmetic mean) weight of two men is x, which is twice

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics

## Events & Promotions

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.