All even numbers from 2 to 98 inclusive, except those ending in 0, are multiplied together what is the rightmost digit (the units digit) of the product?

a) 0
b) 2
c) 4
d) 6

• ans is 6
  first multifly all numbers ending with 2 those are 2*12*22*32*42.......*92=2^10=4 is last digit
  multify all numbers ending with 4=4^10=6 last digit
  multify all numbers ending with 6=6^10= 6 last digit
  multifly all numbers ending with 8=8^10=4 last digit
  so 4*6*6*4=6 last digit
  
• 10 years agoHelpfull: Yes(37) No(7)
• 2^10 * 4^10 * 6^10*8^10 = 2^70 * 3^10
  2^2 * 3^2 = 36
  i.e. ans is = 6
  
• 10 years agoHelpfull: Yes(24) No(4)
• 2*4*6*8 UNIT DIGIT 4---- ------->1
  12*14*16*18 UNIT DIGIT 4----->2
  22*24*26*28 UNIT DIGIT 4----->3
  ---------
  92*94*96*98 UNIT DIGIT 4------>10
  SO 4^10 UNIT DIGIT 6.. AS 4^N GIVES UNIT DIGIT 4 WHEN N IS ODD AND GIVES UNIT DIGIT 6 WHEN N IS EVEN
  
  SO ANS -->6
• 9 years agoHelpfull: Yes(11) No(0)
• 2^10 * 4^10 * 6^10 * 8^10
  
  2^10 (1 * 2 * 3 * 4) = 2^10 * 24
  
  1024 * 24 = _____6 so that 6 is unit digit
• 10 years agoHelpfull: Yes(5) No(1)
• 2^10=1024........unit digit of right side is 4
  4^10=1048576....unit digit of right side is 6
  6^10=60466176.....unit digit of right side is 6
  8^10=1073741824...unit digit of right side is 4
  so 4*6*6*4=576....unit digit of right side=6
• 9 years agoHelpfull: Yes(3) No(0)
• 4 ans .......................
• 10 years agoHelpfull: Yes(2) No(7)
• ans will be 0 . because from 2 to 98 there are so many numbers whose unit digits are 2 and 5 ... if we multiply those numbers the unit digits will be 0 . now a no having unit digit 0 is multiply with any number gives the result having unit digit 0 ....
• 10 years agoHelpfull: Yes(2) No(36)
• (2^10) * (4^10) * (6^10) * (8^10)
  = 4 * 6 * 6 * 4 (unit digit for 2^10 is 4 ...similarly unit digit for 4^10 is 6 etc. )
  = 6 (final unit digit)
• 10 years agoHelpfull: Yes(2) No(1)
• It is very simple.
  2,4,6,8 the product of this numbers gives the unit digit of 4
  similarly 12,14,16,18 gives unit digit of 4.
  4*4*4*4*4*4*4*4*4*4 gives the unit digit of 6. 6 is the correct answer
• 8 years agoHelpfull: Yes(2) No(0)
• 2 ans
  
  (2*4)=8
  
  6*8*12*14**16*18*22*24**....98 --> last digit 4
  
  overall last digit= 8*4 --> 2
• 10 years agoHelpfull: Yes(1) No(11)
• ans should be 4 because digit can be end with 2,4,6,8 only so 4
  
• 10 years agoHelpfull: Yes(1) No(7)
• 2 4 6 8
  12 14 16 18
  20 24 26 28
  .
  .
  .
  .
  92 94 96 98
  
  2*4*6*8 (=384) at units place for one set of four number in the table is multiplied and total 10 time such multiplication will take place
  ie 384*384*384...10times ie 384^10
  
  cylicity of 4 at unit place means it end with 4 or 6 when even power its 6
  
  thereofre 6
• 8 years agoHelpfull: Yes(1) No(0)
• 2*4*6*8*12*14**16*18.............98
  so the unit digit is 4.
  ans. 4.
• 10 years agoHelpfull: Yes(0) No(6)
• I don't know but it seems the answer is 0
  
  Just run this code in java..
  
  import java.math.*;
  
  public class MyClass {
  public static void main(String args[]) {
  
  BigInteger a=new BigInteger("1");
  
  for(int i=2;i
• 6 years agoHelpfull: Yes(0) No(0)