EASY
Earn 100

How many numbers consisting of digits can be formed in which the digits are used only once and the digit is used twice?
(a)30
(b)60
(c)45
(d)90

88.89% studentsanswered this correctly
Important Questions on Permutation and Combination
MEDIUM

EASY
In how many ways the letters of word 'MACHINE' can be arranged so that vowels will always be together?

EASY
If the number of all possible permutations of the letters of the word in which the repeated letters are not together is
, then

MEDIUM

MEDIUM

EASY

MEDIUM

MEDIUM

EASY

MEDIUM

MEDIUM

MEDIUM

EASY

EASY

MEDIUM

MEDIUM

EASY
How many numbers of four digits can be made by using the digits and ? (Repetition of digits is not allowed)

EASY

MEDIUM

