Question

The sum of all the four digit numbers that can be formed with 0, 2, 3, 5 is
1) 66660
2) 66480
3) 64440
4) 65520
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Answer 1

Answer:

Let us consider numbers which include 0 in the first place

Now, sum of all four digit numbers formed = Sum of all numbers − Sum of numbers with 0 in the first place.

Sum of all the numbers =6(2+3+5+0)(1000+100+10+1)=66660

Sum of numbers with 0 in first place =2(2+3+5)(100+10+1)=2220

Hence, the answer =66660−2220=64440.

Answer 2

Answer:

3

(4−1)!(0+2+3+5)(1111)−(4−2)!(0+2+3+5)(111)=3!×10×1111−2!×10×111=64440