(i) Find the number of four letter word that can be formed from the le...
With a vowel and end with a consonant?
(i) To find the number of four-letter words that can be formed from the letters of the word "HISTORY," we can use the concept of permutations. Since each letter can only be used at most once, we need to select 4 out of the 7 available letters. This can be done in 7P4 ways.
7P4 = 7! / (7-4)! = 7! / 3! = 7 * 6 * 5 * 4 = 840
Therefore, there are 840 four-letter words that can be formed from the letters of the word HISTORY.
(ii) To find the number of four-letter words that contain only consonants, we need to consider the consonants in the word HISTORY. The consonants in the word HISTORY are H, S, T, and R. We need to select 4 out of these 4 consonants, which can be done in 4P4 ways.
4P4 = 4! / (4-4)! = 4! / 0! = 4 * 3 * 2 * 1 = 24
Therefore, there are 24 four-letter words that contain only consonants.
(iii) To find the number of four-letter words that begin with a vowel and end with a consonant, we need to consider the vowels and consonants in the word HISTORY. The vowels in the word HISTORY are I and O, and the consonants are H, S, T, and R.
The number of four-letter words that begin with a vowel and end with a consonant can be found by multiplying the number of choices for the first letter (2 vowels) by the number of choices for the second letter (5 letters, since we can choose from all the letters except the first letter), by the number of choices for the third letter (4 letters, since we can choose from all the letters except the first and last letters), and finally by the number of choices for the last letter (4 consonants).
2 * 5 * 4 * 4 = 160
Therefore, there are 160 four-letter words that begin with a vowel and end with a consonant.
(i) Find the number of four letter word that can be formed from the le...
A.7P4
B.5P4
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