A student is to answer 10 out of 13 questions in an examination such that he must choose at le...........

Quantitative Aptitude ( CCS) Permutation & Combination

A student is to answer 10 out of 13 questions in an examination such that he must choose at least 4 from the first five questions. The number of choices available to him is ?

140

280

196

346

छोटे Courses बड़े Results

Master Permutation & Combination

Prepare through Micro-courses

Try Now

Explanation:

If the student answers 4 questions from the first five questions he can choose 6 questions from the remaining 8 questions. Therefore number of combinations will be:
5C4×8C6 = 140
If the student answers 5 questions from the first five questions he can choose 5 questions from the remaining 8 questions. Which will be:
5C5×8C5 = 56
Therefore total number of choices= 140+56=196