5. Five mark example problems

1. Two dice are rolled together. Find the probability of getting a doublet or sum of faces as \(4\).

 

Answer:

 

The probability of getting a doublet or sum of faces as \(4\) is $\frac{i}{i}$.

 

2. A card is drawn from a pack of \(52\) cards. Find the probability of getting a king or a heart or a red card.

 

Answer:

 

The probability of getting a king or a heart or a red card is $\frac{i}{i}$.

 

3. In a class of \(50\) students, \(28\) opted for NCC, \(30\) opted for NSS and \(18\) opted both NCC and NSS. One of the students is selected at random.

 

Find the probability that:

 

(i) The student opted for NCC but not NSS \(=\) $\frac{i}{i}$

 

(ii) The student opted for NSS but not NCC \(=\) $\frac{i}{i}$

 

(iii) The student opted for exactly one of them \(=\) $\frac{i}{i}$