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Numerical Ability
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unit digit of 124^123!
Read Solution (Total 18)
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- ans:6
as 123! is in form of 4n
- 11 years agoHelpfull: Yes(37) No(10)
- 4^even power=6
- 11 years agoHelpfull: Yes(14) No(4)
- ans is 4.
sol-
124^(123!)= 124^123+124^122+124^121+......124^1
=sum of unit digit of all terms
= 4+6+4+6+4+6+.......+4
= 10*61+4
= 614
hence ans is 4. - 11 years agoHelpfull: Yes(13) No(28)
- unit digit is 4
- 11 years agoHelpfull: Yes(10) No(14)
- unit place 6
- 11 years agoHelpfull: Yes(9) No(3)
- i think its 4.. 123! last 2 digits are 00 that's why divisible by 4 .. so no reminder left .. so its 4
- 11 years agoHelpfull: Yes(4) No(12)
- unit digit is 4
Explanation:
For this type of problem, remember the following steps :
1> look at the unit digit of 124 = 4
2> 4^1=4 ,4^2=16,4^3=64,4^4=256.....so on.. Here,we can see that we get the sequence of 4,6,4,6,....as the unit digit repeatedly after 2 times .
3> Now,divide 123%2=1(get the remainder as 1)
4> 4^1=4
- 11 years agoHelpfull: Yes(4) No(3)
- u donno a SHIT.TO THOSE GUYS WHO IS SAYNG 4...FIRST GET UR FACTS STRAIGHT.ITS 6...OPEN CALCULATOR and do the miracle.idiot
- 11 years agoHelpfull: Yes(4) No(0)
- 123! contains many 0' at the end...so 123! is a even number..so,,if we think
124 ^ even..then unit digit is 6 because 4's cycle is like 4,6,4,6,4,6. - 11 years agoHelpfull: Yes(4) No(0)
- 4 TO THE POWER EVEN WILL BE ALWAYS 6 !!!
- 11 years agoHelpfull: Yes(3) No(2)
- It is not soo complex as many of them explained. Remember factorial of all the numbers except 1 is always even. and four raised to ever number always ends with 6. so ans is 6.
- 9 years agoHelpfull: Yes(1) No(0)
- I have a simplest way
we have 123!
Now take last two Digit of the Number is 23!
now divide it by 4...
23!/4= Remainder 3 right
then find 3!
we know the 3! is 6 so Ans is 6.
- 9 years agoHelpfull: Yes(1) No(0)
- 2
as123=4n+3
for ! unitdigit*7,,,
here6*7
so unit digit =2 - 9 years agoHelpfull: Yes(0) No(3)
- Ans is 6
because we just need to calculate 4^123!
and 123! trailing more than two zeroes...
then just dividing last two zeroes by 4, the rem=0 i.e the last digit of the cycle i.e 4..
so 4^4 is 256...
so the last digit is 6.. - 9 years agoHelpfull: Yes(0) No(0)
- 4^3=64
unit digit 4 - 9 years agoHelpfull: Yes(0) No(1)
- 4^even power=6 and 4^odd power=4.
- 9 years agoHelpfull: Yes(0) No(0)
- 123/4=30+3 so for odd places unit digit is 4
ANS =4 - 9 years agoHelpfull: Yes(0) No(0)
- (124)^123!=(31*4)^123!
31*4=124
hence Unit place is 4 - 9 years agoHelpfull: Yes(0) No(0)
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