Sn=1^8+2^8+3^8+----------n^8
find the unit digit of S29

• unit digit of-
  1^8=1
  2^8=6
  3^8=1
  4^8=6
  5^8=5
  6^8=6
  7^8=1
  8^8=6
  9^8=1
  
  so 1+6+1+6+5+6+1+6+1=33 so from here we get 3 as unit digit for 1^8+2^8+.....+9^8
  
  now for 11 to 19 same way unit digit is 3
  then from 21 to 29 unit digit is 3
  so 3+3+3=9
  
  so unit digit is 9
• 8 years agoHelpfull: Yes(17) No(1)
• unit digit will be 9
• 9 years agoHelpfull: Yes(10) No(0)
• S29^8= 29^8
  9^8=9*9*9*9*9*9*9*9
  we know 9*9=81
  So even number of 9 when multiplied together give 1 in unit place so unit digit for s29 is 1
  ans-1
• 9 years agoHelpfull: Yes(5) No(10)
• Unit digit will be 9. Use Cyclicity principle.
• 9 years agoHelpfull: Yes(2) No(0)
• Crypto Was:
  X D L
  H A E
  -----------
  D E P H
  3 P K P
  __ A D __
  ------------
  P __ __ K D H I AM UNABLE TO FLASH BACK THE EXACT 2 CHARACTERS SO I LEFT BLANK.BUT I AM GIVING THE EXACT SOLUTION OF THE ABOVE CRYPTO:
  
  5 4 7
  3 6 9
  ________
  4 9 2 3
  3 2 8 2
  1 6 4 1
  ___________
  2 0 1 8 4 3 SO SIMPLY YOU HAVE TO PUT THE VALUE OF 1 AND 0.I CAN'T CALL BACK THE VALUE OF 0
  AND 1.
  Q.1 WAS:D*H*E=4*3*9=108
  Q.2 WAS:P*D*K=2*4*8= 64
  Q.3 WAS:X*P*__=5*2*1= 10 THE VALUE OF 1 CAN'T CALL FRIENDS.
  
• 9 years agoHelpfull: Yes(2) No(0)
• unit digit of 1^8=1
  unit digit of 2^8=6
  unit digit of 3^8=1
  unit digit of 4^8=6
  ;;;;;;;
  
  similarly find up to 9^8=1
  similar for 11 to 19 also and similar for 21 to 29 also then add all the unit digits. then ans will be 9
• 9 years agoHelpfull: Yes(2) No(0)
• Any even no raised to any power which is multiple of 4 that is (even no)^(4 n) gives 6 as the unit digit while any odd no raised to any power which is multiple of 4 gives 1 as the unit digit.Exception to the above rules are (0,1,5,6).
  Unit digit of :
  1^8= 1
  2^8=6(even no having power multipe of 4)
  3^8=1(odd no having power multiple of 4)
  ...similarly upto 29^8
  3 Number having 5 as unit digit are
  5^8=5
  15^8=5
  25^8=5
  Number having 0 as unit digit are:
  10^8=0
  20^8=0
  No having 1 and 6 as unit digit are 29- (no having 0 and 5 as unit digit)=29-5=24
  Now, Number having 1 and 6 as the unit digit are alternately so they must be 12 and 12 in pairs.
  Sum of all the no having 1 and 6 as unit digit:
  Sum of No having 1 as unit digit=12*1=12
  Sum of no having 6 as unit digit=12*6=72
  No having 5 as unit digit=3
  sum=5*3=15
  No having 0 as unit digit=2
  Their sum=0
  Total sum of all unit digit no from 1^8 to 29^8=12+72+15+0=99
  So, unit digit of S^29=9
• 8 years agoHelpfull: Yes(1) No(0)
• Unit digit will be 9 .all the unit digit form 1^3to9^3will multiplied for times like 1^3*3+2^3×3.....
  =3+8....till unit digit of 9^3 *3
  =9answer
• 9 years agoHelpfull: Yes(0) No(0)
• i cant understand this solution...anyone give an explanation..how ans will come 9....
• 9 years agoHelpfull: Yes(0) No(0)
• Any even number multiple of 4 always gives 6 as unit digit while any odd number multiple of 4 always gives
  1 as the unit digit.In the above question ,we have to find unit digit of S29.
  #Alternately ,we get 1 and 6 as the unit digit upto S29.(that is 1+6+1+6+1.....)
  Now, since no are continuous so no of 1's digit in 1 to 29 will be 29-1=28 and divide by 2=14(we are subtracting 1 as total no upto 29 is odd so to form pair we do so and add 1 ) .14+1=15
  No of number containing 1 as unit digit =15 and 29-15=14 are the no containing 6 as the unit digit.
  Afterthat , calculate the sum of all 15 no having 1 as unit digit=15
  sum of all 14 no having 6 as unit digit=84
  Lastly, add the values 15+84=99
  So, unit digit of S29=9
• 8 years agoHelpfull: Yes(0) No(0)
• unit digit of 1^8 = 1
  similarly 2^8=6
  3^8=1
  4^8=6
  5^8=5
  6^8=6
  7^8=1
  8^8=6
  9^8=1
  10^8=0
  addition=33
  ...so on
  above repeats for 11.......29
  33+33+33=99/10
  reminder=9
• 8 years agoHelpfull: Yes(0) No(0)
• A=18
  b=10
  c=2
  put these values get a answer, after solve a question get these values
• 8 years agoHelpfull: Yes(0) No(0)