Question: Out of 7 consonants and 4 vowels, how many words of 3 consonants and 2 vowels can be formed?
[A].
210 |
[B].
1050 |
[C].
25200 |
[D].
21400 |
Answer: Option C
Explanation:
Number of ways of selecting (3 consonants out of 7) and (2 vowels out of 4)
| |
= (7C3 x 4C2) |
|
| = |
|
7 x 6 x 5 |
x |
4 x 3 |
|
| 3 x 2 x 1 |
2 x 1 |
|
|
= 210. |
Number of groups, each having 3 consonants and 2 vowels = 210.
Each group contains 5 letters.
Number of ways of arranging 5 letters among themselves |
= 5! |
|
= 5 x 4 x 3 x 2 x 1 |
|
= 120. |
Required number of ways = (210 x 120) = 25200.
Video Explanation: https://youtu.be/dm-8T8Si5lg