Defective Bottles

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Defective Bottles

by harsh.champ » Wed Feb 17, 2010 5:45 am
If a bottle is to be selected at random from a certain collection of bottles, what is the probability that the bottle will be defective?


(1) The ratio of the number of bottles in the collection that are defective to the number that are not defective is 3:500.
(2) The collection contains 3,521 bottles.
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by ajith » Wed Feb 17, 2010 6:35 am
harsh.champ wrote:If a bottle is to be selected at random from a certain collection of bottles, what is the probability that the bottle will be defective?


(1) The ratio of the number of bottles in the collection that are defective to the number that are not defective is 3:500.
(2) The collection contains 3,521 bottles.
1) That's exactly what we are looking for, defective % = 3/500*100 = 0.6% ; probability of picking a defective = 3/500; sufficient
2) Insufficient

Hence A
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by shashank.ism » Sun Feb 21, 2010 6:25 pm
harsh.champ wrote:If a bottle is to be selected at random from a certain collection of bottles, what is the probability that the bottle will be defective?


(1) The ratio of the number of bottles in the collection that are defective to the number that are not defective is 3:500.
(2) The collection contains 3,521 bottles.
The ratio of the number of bottles in the collection that are defective to the number that are not defective is 3:500.
St.1) so ratio of the number of bottles in the collection that are defective to the total no. of bottles = 3:503
so probability (defective) = 3/503 .........sufficient

ajith I think u have done a mistake here in ur soln 3/500. you will have to first add both defectiva and non defective and then find the ratio of non defective out of total.
St.2) total no. of bottles is known but not about defective and no-defective no.
so insufficient ...

Ans A
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by ajith » Sun Feb 21, 2010 7:40 pm
shashank.ism wrote:
ajith I think u have done a mistake here in ur soln 3/500. you will have to first add both defectiva and non defective and then find the ratio of non defective out of total.
Agreed, Answer doesn't change anyway.
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