Case-Study4 marksYear: 2025MediumCBSE Class 10
probabilitycase-studyeven-odd-numbersprime-numbers
Question
**Case Study - 2**
Rahul is a lucky charm for his cricket team. He has a jar of cards with numbers from 10 to 74. Before each match, he draws a card from the jar. If the card bears an even number, the team wins. If the number is even and divisible by 5, they win by a big margin. If the number is an odd number less than 30, they win by a small margin. And if the number is a prime number between 50 and 74, they lose.

Answer the following questions if Rahul draws a card today:
(i) What is the probability that Rahul draws a card with an even number?
(ii) What is the probability that Rahul draws a card with an odd number less than 30?
(iii) (a) What is the probability that Rahul draws a card with a prime number between 50 and 74?
**OR**
(iii) (b) What is the probability that Rahul draws a card with an even number divisible by 5? Solution
1
(i) Total possible outcomes =74−10+1=65.
Even numbers from 10 to 74: 10,12,14,…,74. Number of even numbers =33.
P(even number) =6533
+1 mark2
(ii) Odd numbers less than 30 from 10 to 74: 11,13,15,17,19,21,23,25,27,29. Count =10.
P(odd number less than 30) =6510=132
+1 mark3
(iii)(a) Favourable outcomes are 53,59,61,67,71,73. Number of favourable outcomes =6.
P(prime number between 50 and 74) =656
+1 mark4
(iii)(b) Favourable outcomes are 10,20,30,40,50,60,70. Number of favourable outcomes =7.
P(even number divisible by 5) =657
+1 mark