Book Maths Puzzle Numerical Ability

find the sum of all the numbers that can be formed with the digits 2,3,4,5 taken all at a time ?

ans - 93324

Read Solution (Total 3)

the average number in each digit position will be (2+3+4+5)/4 = 14/4 = 7/2. There are 24 permutations. So we get a sum of (24*7/2) = 84 in each position, which means the total is 84+840+8400+84000 = 93324.
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