First slide

Combinations

Question

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

Easy

A

196
B

280
C

346
D

140

Solution

Required number of choices $=^{5} C_{4} \times^{8} C_{6} +^{5} C_{5} \times^{8} C_{5} = 140 + 56 = 196$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App