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Numerical Ability
Permutation and Combination
All possible Five digit number can be formed of 1,3,5,7,9 without any repetition. What will be the sum of the all numbers
Read Solution (Total 17)
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- total no. formed = 5! =120
24 no.s starting with each digit 1,3,5,7,9
sum of digits starting with 1,3,5,7,9 = 24*(1+3+5+7+9) = 24*25 = 600
this sum will be same for thousand, hundred, tens & unit places
sum of all 5 digit numbers formed using digits 1,3,5,7,9
= 10000*600 + 1000*600 +100*600 + 10*600 + 600
= 600*(10000+1000+100+10+1)
= 600 * 11111
= 6666600
use formula
(1111......n) *( sum of digits ) *(n-1)!
here n = 5 - 10 years agoHelpfull: Yes(43) No(3)
- The total 5 digit numbers that can be formed with the given digits are 5*4*3*2*1=120 numbers.
Now, the numbers that will be formed with the given digits in ascending order would be 13579, 13597, 13759 ........and so on........till .... 97351, 97513, 97531.
Now if u add the smallest and the largest of the numbers formed with the given digits (i.e 13579+97531) their sum would be 111110.
Now is u add the 2nd number and the 2nd last number (i.e 13597+97513) their sum will also be ..... 111110.
similarly, if u add the 3rd number and the 3rd last number ( i.e 13759 + 97351) their sum would also be 111110.
so the answer would be 111110*60=6666600 - 10 years agoHelpfull: Yes(12) No(0)
- 11111*(1+3+5+7+9)*4!
11111*(25)*24
6666600
- 10 years agoHelpfull: Yes(9) No(0)
- 6666600 is the ans.....
- 10 years agoHelpfull: Yes(3) No(1)
- Logic is (n-1)P(r-1)*(111111.......r times)*(sum of digits)............n=number of digits given,r=r digit number
- 10 years agoHelpfull: Yes(2) No(1)
- its so simple when ever u c dis type
go for it
11111(1+3+5+7+9)*(5-1)!=6666600 - 10 years agoHelpfull: Yes(2) No(0)
- PALLAVI PLZZ GIVE UR NO........:)
- 9 years agoHelpfull: Yes(2) No(0)
- @ SAUMYADIP MOITRA plz plz explain how????????
- 10 years agoHelpfull: Yes(1) No(2)
- total no. formed = 5! =120
24 no.s starting with each digit 1,3,5,7,9
sum of digits starting with 1,3,5,7,9 = 24*(1+3+5+7+9) = 24*25 = 600
this sum will be same for thousand, hundred, tens & unit places
sum of all 5 digit numbers formed using digits 1,3,5,7,9
= 10000*600 + 1000*600 +100*600 + 10*600 + 600
= 600*(10000+1000+100+10+1)
= 600 * 11111
= 6666600 - 10 years agoHelpfull: Yes(1) No(0)
- A three digit number was divided successively in order by 4, 5 and 6 leaving out the remainders. The
remainders were respectively 2, 3 and 4. How many such three digit numbers are possible? - 10 years agoHelpfull: Yes(0) No(1)
- 5!(11111)(25)
- 10 years agoHelpfull: Yes(0) No(3)
- If repition is not allowed then sum of all will be
[(nā1)!*(111...ntimes)*(Sum of the digits)] ā [(nā2)!*(111...(nā1)times)*(Sum of the digits)]
[(5-1)!]*(11111)*(1+3+5+7+9) - [(5-2)!]*(1111)*(1+3+5+7+9)
6666600 - 166650
6499950 - 10 years agoHelpfull: Yes(0) No(2)
- logic is: the give nos(i.e 5..1,3,5,7,9) * (nos-1 ,i.e ..5-1=4)! * (sum of all the digits i.e., 1+3+5+7+9)
=6666600 - 10 years agoHelpfull: Yes(0) No(0)
- total no. formed = 5! =120
24 no.s starting with each digit 1,3,5,7,9
sum of digits starting with 1,3,5,7,9 = 24*(1+3+5+7+9) = 24*25 = 600
this sum will be same for thousand, hundred, tens & unit places
sum of all 5 digit numbers formed using digits 1,3,5,7,9
= 10000*600 + 1000*600 +100*600 + 10*600 + 600
= 600*(10000+1000+100+10+1)
= 600 * 11111
= 6666600
- 9 years agoHelpfull: Yes(0) No(0)
- sum=sum of digit*(d-1)!*11111
sum=25*(5-1)!*11111
sum=25*24*11111
sum=6666600 - 9 years agoHelpfull: Yes(0) No(0)
- ans: sum=666660
- 9 years agoHelpfull: Yes(0) No(0)
- sum=sum of digit*(d-1)!*11111
sum=25*(5-1)!*11111
sum=25*24*11111
sum=6666600..is correct.lock kr do - 9 years agoHelpfull: Yes(0) No(0)
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