JEE Main 2014 (Online) 12th AprilQuestion 1
A number $x$ is chosen at random from the set $\{1,2,3,4,\ldots,100\}$. Define the event $A$ = the chosen number $x$ satisfies $\frac{(x-10)(x-50)}{(x-30)}\ge0$. Then $P(A)$ is :
Probability
Solution
For $x\ne30$ the expression is $\ge0$ for $10\le x<30$ (20 values), $x=50$ (1 value) and $x>50$ (50 values). Total $71$, so $P(A)=0.71$.