two friends A and B have equal number of sons there are three cinema tickets which are to be distributed - Maths - Probability

Question

two friends A and B have equal number of sons there are three
cinema tickets which are to be distributed among the sons Of A and
B the probability that all the tickets go to the sons of B is 1/20
the number of sons each of them having is

Shruti Tyagi · Accepted Answer

Dear student,

Let  total no
 of sons be nTotal possible combination among n sons=C3n=20⇒n!3!n-3!=20⇒n×(n-1)×(n-2)×n-3!3!×n-3!=20⇒n×(n-1)×(n-2)=6×20n×(n-1)×(n-2)=6×5×4Hence n=6, n-1=5 and n-2=4Thus total number of sons=n=6as both A and B have equal number of sonshence number of sons each A and B having=62⇒3Answer is 3
Regards,

two friends A and B have equal number of sons there are three cinema tickets which are to be distributed among the sons Of A and B the probability that all the tickets go to the sons of B is 1/20 the number of sons each of them having is