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Interesting problems..Needed help!!
by nikhil rao - Saturday, 13 October 2012, 10:39 AM
  Hey guys pls help me to solve problems of these kind..
Sorry for not having the exact numerical.

1. It goes like this. Half life of a radio active element is 3700 years(X years).The present activity is 680 gms per decay(Y gms per decay) ,its activity Z months back was A gms per decay. Calculate the life of that radio active element.
(I have mentioned X Y Z A coz i do not remember exact question since it was asked in an interview)

2. There are two bags containing balls. Any bag can be chosen randomly.First bag has 4 red and 5 white , second bag contains 2 red and 3 white balls. What is probability of picking exactly one white ball?






Re: Interesting problems..Needed help!!
by jmen tg - Tuesday, 16 October 2012, 11:37 PM
  for qs 2, i think it is (1/2*5/9)+(1/2*3/5)=5/18+3/10

1/2 is probability of selecting the bag and the rest is probability of selecting the white ball.