A problem is given to three students A, B and C, whose probabilities of solving the problem independently are \(\rm \frac{1}{2}\)\(\rm \frac{3}{4}\) and p respectively. If the probability that the problem can be solved is \(\rm \frac{29}{32}\), then what is the value of p?

This question was previously asked in
NDA 02/2021: Maths Previous Year paper (Held On 14 Nov 2021)
View all NDA Papers >
  1. \(\rm \frac{2}{5}\)
  2. \(\rm \frac{2}{3}\)
  3. \(\rm \frac{1}{3}\)
  4. \(\rm \frac{1}{4}\)

Answer (Detailed Solution Below)

Option 4 : \(\rm \frac{1}{4}\)
Free
NDA 01/2025: English Subject Test
5.5 K Users
30 Questions 120 Marks 30 Mins

Detailed Solution

Download Solution PDF

Formula used:

Probability: The probability of an event can be calculated by simply

dividing the favorable number of outcomes by the total number

of possible outcomes.

The value of the probability of an event to happen can lie between 0 and 1 i.e. P(̅{E})

P(E)+P(̅{E}) = 1

\(\rm P(E) + P(\overline{E}) = 1\)

The event \(\rm P(\overline{E}) \) means ‘Not E’.

Calculation:

P(problem is solved) = 1 - P(problem is not solved)

⇒ P(problem is solved) = 1 - P(A̅) × P(B̅) P(C̅)

⇒ \(\rm (\frac{29}{32}) = 1-(1 - \frac{1}{2})(1 - \frac{3}{4})(1 - p)\)

⇒ \(\rm (1 - \frac{29}{32}) = (1 - \frac{1}{2})(1 - \frac{3}{4})(1 - p)\)

⇒ \(\rm \frac{3}{32} = \frac{1}{2}× \frac{1}{4} × (1 - p)\)

⇒ 1 - p = \(\rm \frac{3}{4}\)

⇒ P = 1 - \(\rm \frac{3}{4}\)

⇒ P = \(\rm \frac{1}{4}\)  

∴ The value of p is \(\rm \frac{1}{4}\).

Latest NDA Updates

Last updated on Jun 18, 2025

->UPSC has extended the UPSC NDA 2 Registration Date till 20th June 2025.

-> A total of 406 vacancies have been announced for NDA 2 Exam 2025.

->The NDA exam date 2025 has been announced. The written examination will be held on 14th September 2025.

-> The selection process for the NDA exam includes a Written Exam and SSB Interview.

-> Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100. 

-> Candidates must go through the NDA previous year question paper. Attempting the NDA mock test is also essential. 

More Probability of Random Experiments Questions

More Probability Questions

Get Free Access Now
Hot Links: dhani teen patti teen patti real cash teen patti online game all teen patti master