JEE AdvancedPermutation and CombinationMediumBloom L3
Question
Ten different letters of an alphabet are given. Words with five letters are formed from these given letters. Then, the number of words which have at least one letter repeated, is
Options
A.69760
B.99748
C.30240
D.None of these
Solution
Total number of five letters words formed from ten different l
letters = 10 × 10 × 10 × 10 × 10 = 105
Number of letters words having no repetition = 10 × 9 × 8 × 7 × 6 = 30240
∴ Number of words have at least one letter repeated
= 105 - 30240 = 69760
letters = 10 × 10 × 10 × 10 × 10 = 105
Number of letters words having no repetition = 10 × 9 × 8 × 7 × 6 = 30240
∴ Number of words have at least one letter repeated
= 105 - 30240 = 69760
Create a free account to view solution
View Solution FreeMore Permutation and Combination Questions
The total number of donations which can be given from 5 one rupee coins and 4 fifty paise coins, is (at least one coin m...Two variants of a test paper are distributed among 12 students. Number of ways of seating of the students in two rows so......2nPn is equal to...All possible two factors products are formed from numbers 1, 2, 3, 4, ........, 200. The number of factors out of the to...