JEE Mains · Maths · STD 11 - 6. permutation and combination
The sum of the digits in the unit's place of all the \(4-\) digit numbers formed by using the numbers \(3, 4 , 5\) and \(6\), without repetition, is
- A \(432\)
- B \(108\)
- C \(36\)
- D \(18\)
Answer & Solution
Correct Answer
(B) \(108\)
Step-by-step Solution
Detailed explanation
With \(3\) at unit place, total possible four digit number (without repetition) will be \(3! = 6\) With \(4\) at unit place, total possible four digit numbers will be \(3! = 6\) With \(5\) at unit place, total possible four digit numbers will be \(3!=6\) With \(6\) at unit…
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