Out of 40 consecutive natural numbers,two are | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) In a set of $40$ consecutive natural numbers,there are $20$ odd numbers and $20$ even numbers.For the sum of two numbers to be odd,one must be eve

Vedclass · Accepted Answer

$\frac{20}{39}$

Vedclass · Answer

(B) In a set of $40$ consecutive natural numbers,there are $20$ odd numbers and $20$ even numbers.For the sum of two numbers to be odd,one must be even and the other must be odd.The total number of ways to choose $2$ numbers from $40$ is $^{40}C_2 = \frac{40 	imes 39}{2} = 780$.The number of ways to choose one odd number and one even number is $^{20}C_1 	imes ^{20}C_1 = 20 	imes 20 = 400$.The required probability is $P = \frac{400}{780} = \frac{40}{78} = \frac{20}{39}$.

Out of $40$ consecutive natural numbers,two are chosen at random. The probability that the sum of the numbers is odd is:

Similar Questions

Three dice are rolled. If the probability of getting different numbers on the three dice is $\frac{p}{q}$,where $p$ and $q$ are co-prime,then $q-p$ is equal to

The probability of forming a $12$-person committee from $4$ engineers,$2$ doctors,and $10$ professors containing at least $3$ engineers and at least $1$ doctor is:

$A$ bag contains $3$ red,$7$ white and $4$ black balls. If three balls are drawn from the bag,then the probability that all of them are of the same colour is

$A$ committee of $5$ is to be formed from a group of $9$ people. What is the probability that a specific married couple is either both included or both excluded from the committee?

If $A_1, A_2, \ldots, A_{15}$ are the events of a random experiment, then which one of the following is true?

Vedclass Test Series

Exam Paper Generator

Online Exam Module