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

 It is currently 17 Aug 2018, 23:50

### 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

# A new water pump was fixed in a locality of 1200 people. They were ask

Author Message
TAGS:

### Hide Tags

Manager
Joined: 15 Dec 2015
Posts: 120
GMAT 1: 660 Q46 V35
GPA: 4
WE: Information Technology (Computer Software)
A new water pump was fixed in a locality of 1200 people. They were ask  [#permalink]

### Show Tags

04 Feb 2018, 12:51
00:00

Difficulty:

55% (hard)

Question Stats:

68% (03:44) correct 32% (02:17) wrong based on 19 sessions

### HideShow timer Statistics

A new water pump was fixed in a locality of 1200 people. They were asked to give ratings to the purity of new water supply and the old one. The feedback is shown in the table below, more number of stars means better the quality.

If 3 or 2 star rating implies dissatisfaction and 275 people, who gave 5 star rating to old water supply, disliked the new one, how many did not like any of the two?

(A) 225
(B) 250
(C) 500
(D) 550
(E) 650

Attachment:

2018-02-05 01_17_10-Microsoft Office 2010.png [ 334.95 KiB | Viewed 564 times ]
Math Expert
Joined: 02 Aug 2009
Posts: 6548
Re: A new water pump was fixed in a locality of 1200 people. They were ask  [#permalink]

### Show Tags

04 Feb 2018, 19:26
1
DHAR wrote:

A new water pump was fixed in a locality of 1200 people. They were asked to give ratings to the purity of new water supply and the old one. The feedback is shown in the table below, more number of stars means better the quality.

If 3 or 2 star rating implies dissatisfaction and 275 people, who gave 5 star rating to old water supply, disliked the new one, how many did not like any of the two?

(A) 225
(B) 250
(C) 500
(D) 550
(E) 650

Attachment:
2018-02-05 01_17_10-Microsoft Office 2010.png

More likely to be an IR question..
we have 275 out of 450 who gave 5-star rating to only OLD ..
so the dissatisfied customers of new will contain this 275..
so number of people dissatisfied with both = number of dissatisfied with new - 275 = 225+600-275=550

D
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

GMAT online Tutor

Manager
Joined: 27 Jun 2015
Posts: 66
WE: Information Technology (Computer Software)
Re: A new water pump was fixed in a locality of 1200 people. They were ask  [#permalink]

### Show Tags

05 Feb 2018, 19:49
chetan2u wrote:
DHAR wrote:

A new water pump was fixed in a locality of 1200 people. They were asked to give ratings to the purity of new water supply and the old one. The feedback is shown in the table below, more number of stars means better the quality.

If 3 or 2 star rating implies dissatisfaction and 275 people, who gave 5 star rating to old water supply, disliked the new one, how many did not like any of the two?

(A) 225
(B) 250
(C) 500
(D) 550
(E) 650

Attachment:
2018-02-05 01_17_10-Microsoft Office 2010.png

More likely to be an IR question..
we have 275 out of 450 who gave 5-star rating to only OLD ..
so the dissatisfied customers of new will contain this 275..
so number of people dissatisfied with both = number of dissatisfied with new - 275 = 225+600-275=550

D

Hi chetan2u,
Thanks for the explanation.
But I can't get around the logic here. No. of dissatisfied with new = 825.
275 cust have given 5-star to only Old, so 275 are dissatisfied with new.
So,how do we know there are customers in '825', who dislike Old?
Also, can you please tell why we are subtracting 275 from 825; how do we know there is redundancy of 275 in 825?
Math Expert
Joined: 02 Aug 2009
Posts: 6548
A new water pump was fixed in a locality of 1200 people. They were ask  [#permalink]

### Show Tags

05 Feb 2018, 20:03
1
chetan2u wrote:
DHAR wrote:

A new water pump was fixed in a locality of 1200 people. They were asked to give ratings to the purity of new water supply and the old one. The feedback is shown in the table below, more number of stars means better the quality.

If 3 or 2 star rating implies dissatisfaction and 275 people, who gave 5 star rating to old water supply, disliked the new one, how many did not like any of the two?

(A) 225
(B) 250
(C) 500
(D) 550
(E) 650

Attachment:
2018-02-05 01_17_10-Microsoft Office 2010.png

More likely to be an IR question..
we have 275 out of 450 who gave 5-star rating to only OLD ..
so the dissatisfied customers of new will contain this 275..
so number of people dissatisfied with both = number of dissatisfied with new - 275 = 225+600-275=550

D

Hi chetan2u,
Thanks for the explanation.
But I can't get around the logic here. No. of dissatisfied with new = 825.
275 cust have given 5-star to only Old, so 275 are dissatisfied with new.
So,how do we know there are customers in '825', who dislike Old?
Also, can you please tell why we are subtracting 275 from 825; how do we know there is redundancy of 275 in 825?

Another way

It is given OLD-
Dissatisfied-50+700=750 ; satisfied-450; Total-1200

NEW-
Dissatisfied-225+600-825; satisfied-375; Total-1200

Now it is given 275 who were satisfied with Old are not satisfied with new.
So 450-275=175 are satisfied with both..
These 175 are in new satisfied also, so those only satisfied with new = 375-175=200..

Total satisfied with atleast 1= $$200+175+275=650..$$
Therefore those not satisfied with any = $$1200-650=550$$..
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

GMAT online Tutor

A new water pump was fixed in a locality of 1200 people. They were ask &nbs [#permalink] 05 Feb 2018, 20:03
Display posts from previous: Sort by

# 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®.