10th Class Mathematics Probability Question Bank Case Based (MCQs) - Probability

Study Case : Q. 31 to 35

Three persons toss 3 coins simultaneously and note the outcomes. Then, they ask few questions to one another.

Help them in finding the answer of the following questions:

The probability of getting almost one tail is:

A) 0

B) 1

C) \[\frac{1}{2}\]

D) \[\frac{1}{4}\]

Correct Answer: C

Solution :

Sample space

\[(S)=\{HHH,HHT,HTH,HTT,THH,THT,TTH,TTT\}\] \[\Rightarrow \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,n(S)=8\]

Let A be the event of getting at most one tail.

\[\therefore \,\,\,\,\,\,\,\,A=\{HHH,HHT,HTH,THH\}\]

\[\Rightarrow \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,n(A)=4\]

\[\therefore \] Required probability \[=\frac{4}{8}=\frac{1}{2}\]

So, Option [c] is correct.