Sum of two positive numbers is 100 . probability that their product is greater than 1000 is

English

Gujarati

Hindi

14.Probability

hard

The sum of two positive numbers is $100$. The probability that their product is greater than $1000$ is

A

$\frac{7}{9}$

B

$\frac{7}{{10}}$

C

$\frac{2}{5}$

D

None of these

Solution

(a) Required pair $ = (12,\,88),(13,\,87)………(88,\,12)$

Total number of such pairs are $77$ and total number of pairs (for which sum is $100 ) = 99$

$\therefore$ Required probability $ = \frac{7}{9}$

Standard 11

Mathematics

Share

Similar Questions

In a single throw of two dice, the probability of obtaining a total of $7$ or $9$, is

easy

In a game, a man wins $Rs.\,100$ if he gets $5$ or $6$ on a throw of a fair die and loses $Rs.\,50$ for getting any other number on the die. If he decides to throw the die either till he gets a five or a six or to a maximum of three throws, then his expected gain/loss (in rupees) is

hard

(JEE MAIN-2019)

A six faced dice is so biased that it is twice as likely to show an even number as an odd number when thrown. It is thrown twice. The probability that the sum of two numbers thrown is even, is

medium

The probability that a marksman will hit a target is given as $1/5$. Then his probability of at least one hit in $10$ shots, is

medium

On her vacations Veena visits four cities $( A ,\, B ,\, C$ and $D )$ in a random order. What is the probability that she visits $A$ just before $B$ ?

medium