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:

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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?