Download the app

Questions  

The chance of one event happening is the square of the chance of a second event, but the odds against the first are cube of the odds against the second. The chance of the first event is

Remember concepts with our Masterclasses.

80k Users
60 mins Expert Faculty Ask Questions
a
13
b
19
c
23
d
49

Ready to Test Your Skills?

Check Your Performance Today with our Free Mock Tests used by Toppers!

detailed solution

Correct option is B

Let the two events be E1 andE2 . Let their chances be p and q respectively. Then p=q2 …………….(i)  The chances of not happening of the events are 1−p and 1−q respectively.Odds against the first event = 1−pp Odds against the second event = 1−qq Given 1−pp  =(1−qq)3⇒1−q2q2=(1−q)3q3[from   (i)] ⇒(1−qq2)[(1+q)−(1−q)2q]=0  ∵q≠1  and  q≠0 ∴q(1+q)=1−2q+q2⇒q=13 ∴ from (i) p=q2=19 ∴p(E1)=p=19


Similar Questions

A coin whose faces are marked 3 and 5 is tossed 4 times. The odds against the sum of the numbers thrown being less than 15 are


whats app icon
phone icon