Question
Question: A student is to answer 10 questions out of 13 questions in an examination such that he has to choose...
A student is to answer 10 questions out of 13 questions in an examination such that he has to choose at least 4 from the first five. In how many ways he can select the answers.
A
140
B
196
C
280
D
346
Answer
196
Explanation
Solution
(Four from first five & Six from remaining)
Or
(Five from first five) & (Five from remaining)
= (5C4 × 8C6) + (5C5 × 8C5)
= (5 × 28) + (1 × 56)