Combination of n Different Things Taken One or More at a Time
You are given...
Question
You are given 7 different consonants and 3 different vowels. You have to form three letter words each containing 2 consonants and 1 vowel so that the vowel is always in between the two consonants. How many such words can be formed?
Open in App
Solution
Con. Vow 7C2×3C1=21×3=63 selection of 3 letter words consisting of 2 consonants and one vowel. Now vowel is to be between the consonants. Hence the arrangement will be only of the consonants i.e. 2! Hence 63×2!=126.