Question

# A ball is drawn at random from box I and transferred to box II. If the probability of drawing a red ball from box I, after this transfer, is 13, then the correct option(s) with the possible values of n1 and n2 is (are)

A
n1=4 and n2=6
B
n1=2 and n2=3
C
n1=10 and n2=20
D
n1=3 and n2=6
Solution
Verified by Toppr

#### Let n1 and n2 be the number of red and black balls, respectively, in box I. Let n3 and n4 be the number of red and black balls, respectively, in box II.Let E3 be the event that transferred ball is red and E4 be the event that transferred ball is black.R be the event of selecting a Red ball.P(R)=P(E3).P(R/E3)+P(E4).P(R/E4)⇒P(R)=13=n1n1+n2.(n1−1n1+n2−1)+n2n1+n2.(n1n1+n2−1)=n1n1+n2only options C and D satisfies the above relation.

2
Similar Questions
Q1

For the Paschen series the values of n1 and n2 in the expression E=RH×c[1n211n22]

View Solution
Q2

For positive integers n1,n2 the value of the expression (1+i)n1+(1+i3)n1+(1+i5)n2 + (1+i7)n2 where i=21 is a real number if and only if

View Solution
Q3

Let n1 and n2 be the number of red and black balls, respectively in box I. Let n3 and n4 be the number of red and black balls, respectively in box II.
A ball is drawn at random from box I and transferred to box II. If the probability of drawing a red ball from box I, after this transfer, is 13, then the correct option(s) with the possible values of n1 and n2 is/are

View Solution
Q4

Let n1 and n2 be the number of red and black balls, respectively in box I. Let n3 and n4 be the number of red and black balls, respectively in box II.
One of the two boxes, box I and box II was selected at random and a ball was drawn randomly out of this box. The ball was found to be red. If the probability that this red ball was drawn from box II, is 13, then the correct option(s) with the possible values of n1,n2,n3 and n4 is/are

View Solution
Q5

An electron in a hydrogen atom makes a transition from n=n1 to n=n2. The time period of the electron in the initial state is eight times that in the final state. The possible values of n1 and n2 are

View Solution
Solve
Guides