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 :
← JEE Main 2014 · 9 Apr · Shift 1
MathematicsSingle correct+4 / -1Question 68 of 90
JEE Main 2014 · 9 Apr · Shift 1, Mathematics question 68
Answer and worked solution
Official answer: B
Each digit appears in the unit's place in of the 24 numbers. So the sum is .
Topics:Permutations