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

 It is currently 10 Dec 2018, 18:47

### 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

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

## Events & Promotions

###### Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
• ### Free lesson on number properties

December 10, 2018

December 10, 2018

10:00 PM PST

11:00 PM PST

Practice the one most important Quant section - Integer properties, and rapidly improve your skills.
• ### Free GMAT Prep Hour

December 11, 2018

December 11, 2018

09:00 PM EST

10:00 PM EST

Strategies and techniques for approaching featured GMAT topics. December 11 at 9 PM EST.

# If a, b, c, d are four integers such that a < b < c < d, Is d-c = c-b

Author Message
TAGS:

### Hide Tags

DS Forum Moderator
Joined: 21 Aug 2013
Posts: 1412
Location: India
If a, b, c, d are four integers such that a < b < c < d, Is d-c = c-b  [#permalink]

### Show Tags

28 Jun 2018, 10:41
3
00:00

Difficulty:

65% (hard)

Question Stats:

50% (02:18) correct 50% (01:40) wrong based on 44 sessions

### HideShow timer Statistics

If a, b, c, d are four integers such that a < b < c < d, Is d - c = c - b ?

(1) All four integers a, b, c, d are less than 5.

(2) Arithmetic mean of a, b, c, d is same as the median of a, b, c, d.
Intern
Joined: 03 Mar 2018
Posts: 31
GMAT 1: 620 Q44 V31
If a, b, c, d are four integers such that a < b < c < d, Is d-c = c-b  [#permalink]

### Show Tags

28 Jun 2018, 12:06
1
amanvermagmat wrote:
If a, b, c, d are four integers such that a < b < c < d, Is d - c = c - b ?

(1) All four integers a, b, c, d are less than 5.

(2) Arithmetic mean of a, b, c, d is same as the median of a, b, c, d.

IMO E

Statement 1: All four integers a, b, c, d are less than 5.

a<b<c<d Lets assume a=1, b=2, c=3, d=4

d-c=4-3=1
c-b=3-2=1 Yes, this satisfies the condition.

Now lets assume a=-10, b-4, c=0, d=1

d-c=1-0=1
c-b=0-(-4)=4 No, this doesn't satisfy the condition.

Therefore, Statement 1 is insufficient.

Statement 2: Arithmetic mean of a, b, c, d is same as the median of a, b, c, d.

Let's assume a=-10, b=-5, c=5, d=10
mean(0/4) = 0 = median(0/2)

d-c=10-5=5
c-b=5-(-5)=10 No, this doesn't satisfy the condition.

Now lets assume a=1, b=2, c=3, d=4
mean (10/4) = 2.5 = (5/2) Median

d-c=4-3=1
c-b=3-2=1 Yes, this satisfies the condition.

Therefore, Statement 2 is insuficient.

Together,
Lets assume a=1, b=2, c=3, d=4
mean (10/4) = 2.5 = (5/2) Median

d-c=4-3=1
c-b=3-2=1 Yes, this satisfies the condition.

Lets assume a=-4, b=-2, c=2, d=4
Median = Mean = 0

d-c=4-2=2
c-b=2-(-2)=4 No, this doesn't satisfy th[/u][/i]e condition.

Even taken Together, the Statements are insufficient to arrive at an answer.

_________________

KUDOS appreciated!

Intern
Joined: 07 Feb 2017
Posts: 16
If a, b, c, d are four integers such that a < b < c < d, Is d-c = c-b  [#permalink]

### Show Tags

28 Jun 2018, 17:45
amanvermagmat wrote:
If a, b, c, d are four integers such that a < b < c < d, Is d - c = c - b ?

(1) All four integers a, b, c, d are less than 5.

(2) Arithmetic mean of a, b, c, d is same as the median of a, b, c, d.

My ans is E

Question asks, whether C is the average of b & d

St1: No valid info to prove or disprove the question

St2: Rearranging we get a+d = b+c

option1 : if a,b,c,d are conseq no., then true.

option2 : a=-8, b=-5, c=-4, d=-1, then false

combining st1 & st2, statement 2 has number choices taken based on statement 1. Still no answer
If a, b, c, d are four integers such that a < b < c < d, Is d-c = c-b &nbs [#permalink] 28 Jun 2018, 17:45
Display posts from previous: Sort by