M4maths
Maths Puzzle
Numerical Ability
find the sum of all number greater than 10000 that can be formed using digits 0,2,3,4,5 if repetition is not allowed.
Read Solution (Total 4)
-
- toal no. formed which is greater than 100000 =4*4*3*2*1
=96;
no. started with only 4 no. i.e 2,3,4,5
sum of no=6(2+3+4+5)(4*10^4+3*10^3+3*10^2+3*10+3);
=6*14*43333
=3639972 - 10 years agoHelpfull: Yes(6) No(1)
- 0,2,3,4,5
numbers must be greater than 10,000 and repitition not allowed
so, we consider only 5 digit numbers
_ _ _ _ _
first digit do not start with 0
so, for first digit we have 4! ways
2nd digit also have 4! ways
(2 numbers are over)
3rd digit-3! ways
4th digit-2! ways
5th-1!
finally 4!*4!*3!*2!*1! ways
=24*24*6*2*1
=6912 - 10 years agoHelpfull: Yes(5) No(3)
- first num does not starts with 0 so
4*5*4*3*2*1=480(since repetation is not allowed) - 10 years agoHelpfull: Yes(0) No(4)
- to find out sum of n-digit numbers formed by digit using x,y,z...upto n digits
=(n-1)!*(x+y+z)*(111...n times )
so let fix 2 at ten thousand place then we have 0,3,4,5 to make 4 digit numbers
so total sum of numbers starting with 2 will be
2*24*10000+3!(0+3+4+5)*1111=48000+6*12*1111=127992
similary for 5
5*24*10000+3!(0+3+4+2)*1111=120000+6*9*1111=179994
similarly for 3
3*24*10000+3!(0+2+4+5)*1111=72000+6*11*1111=145321
similarly for 4
4*24*10000+3!(0+3+2+5)*1111=96000+6*10*1111=162660
so total sum=127992+179994+145321+162660=615697 - 10 years agoHelpfull: Yes(0) No(0)
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