Easy Probability Solved QuestionAptitude Discussion

 Q. In a charity show tickets numbered consecutively from 101 through 350 are placed in a box. What is the probability that a ticket selected at random (blindly) will have a number with a hundredth digit of 2?
 ✖ A. 0.285 ✔ B. 0.40 ✖ C. 100/249 ✖ D. 99/250

Solution:
Option(B) is correct

250 numbers between 101 and 350 i.e. $n(S) = 250$

$n(E) = 100^{th}$ digits of $2= 299-199 = 100$

$P(E) = \dfrac{n(E)}{n(S)}$

$= \dfrac{100}{250}$

$= \textbf{0.40}$

(2) Comment(s)

VShank
()

how 250 number will be in between 101 to 350 ?, its 249 only.

Rimjhim
()

It's 250 only (both 101 and 350 are included). Had we left 101, it would have been 249 tickets.