Algebra

Probability

Easy

common

The probability that a student is not a swimmer is $\frac{1}{5}$ . Then the probability that out of five students, four are swimmers is :

$^5C_4 \left(\frac{4}{5}\right)^4 \frac{1}{5}$

$\left(\frac{4}{5}\right)^4 \frac{1}{5}$

$^5C_4 \left(\frac{1}{5}\right)^4 \left(\frac{4}{5}\right)$

$\left(\frac{1}{5}\right)^4 \left(\frac{4}{5}\right)$

✅ Correct Option: 1

$P(\text{swimmer})=p=4/5$ , $P(\text{not swimmer})=q=1/5$ , $n=5$ , $r=4$ .

Using binomial distribution:

$P(X=4)={}^5C_4\,p^4 q^1={}^5C_4\left(\frac{4}{5}\right)^4\frac{1}{5}$ .

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Two cards are drawn simultaneously from a well shuffled pack of 52 cards. If X denotes the number of Spades in two draws, then

Match the LIST-I with LIST-II

LIST-I		LIST-II
A. $P(X=0)$		I. 1
B. $P(X=1)$		II. $\dfrac{19}{34}$
C. $P(X=2)$		III. $\dfrac{13}{34}$
D. $P(X<3)$		IV. $\dfrac{1}{17}$

Choose the correct answer from the options given below:

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Given that the events A and B are mutually exclusive such that $P(A)=\dfrac{1}{2}$ , $P(A\cup B)=\dfrac{2}{3}$ and $P(B)=p$ , then the value of $p$ is:

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What is the probability that the doctor arrives late ?

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If X is a normal variate with mean 16 and standard deviation 4, then the value of standard normal variate Z corresponding to X = 17 is:

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If answer is correct, the probability that he guesses, is :

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A problem in Mathematics is given to two students X and Y whose chances of solving it are $\frac{1}{3}$ and $\frac{1}{4}$ respectively. The probability that only X solves the problem, is:

The probability that a student is not a swimmer is 15\frac{1}{5}51​. Then the probability that out of five students, four are swimmers is :

Solution

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CUET Mathematics Past Year Questions (Topic-Wise)

The probability that a student is not a swimmer is $\frac{1}{5}$ . Then the probability that out of five students, four are swimmers is :