Aptitude - Numbers - Discussion
Discussion Forum : Numbers - General Questions (Q.No. 10)
10.
What is the unit digit in {(6374)1793 x (625)317 x (341491)}?
Answer: Option
Explanation:
Unit digit in (6374)1793 = Unit digit in (4)1793
= Unit digit in [(42)896 x 4]
= Unit digit in (6 x 4) = 4
Unit digit in (625)317 = Unit digit in (5)317 = 5
Unit digit in (341)491 = Unit digit in (1)491 = 1
Required digit = Unit digit in (4 x 5 x 1) = 0.
Discussion:
123 comments Page 6 of 13.
Kratika said:
1 decade ago
Find unit digit of 1^1!+2^2!+........+80^80.
AMIT KUMAR SINGH said:
1 decade ago
On the basis of cyclicity rule we easily find the unit digit .
4*5*1 = 0.
4^1 =4 5^1 =5 1^1=1.
4^2 =6 5^2 =5 1 cyclicity is 1.
4^3 =4 5 cyclicity is 5.
Cyclicity of 4 is 2.
Then 4^1793 divide 1793/3 = 1 4^1 = 4 as on...
Finally 4*5*1 = 0.
4*5*1 = 0.
4^1 =4 5^1 =5 1^1=1.
4^2 =6 5^2 =5 1 cyclicity is 1.
4^3 =4 5 cyclicity is 5.
Cyclicity of 4 is 2.
Then 4^1793 divide 1793/3 = 1 4^1 = 4 as on...
Finally 4*5*1 = 0.
Vinay said:
1 decade ago
I have for the given problem.
4*5*1= 20 that is unit digit =0;
But for (264)^102*(264)^103 we need to get answer as 4*4 = 16 unit digit as 6,
But in test book they given answer as 0,
How it is please explain me?
4*5*1= 20 that is unit digit =0;
But for (264)^102*(264)^103 we need to get answer as 4*4 = 16 unit digit as 6,
But in test book they given answer as 0,
How it is please explain me?
HIDD said:
1 decade ago
When power is same we can just multiple the unit number, we will get answer.
Shivani said:
1 decade ago
Thanks @Seema. I got your point otherwise all of them make me confuse.
Susmitha said:
1 decade ago
What is the unit digit of {3^65*6^59*7^71}? Please can anyone explain me the answer?
Vidhya said:
1 decade ago
How to find easy way to answer the question?
Abhignareddy said:
1 decade ago
(2467)^153*(341)^72 solve this please.
Neeha said:
1 decade ago
Please explain in briefly.
Suryasish said:
1 decade ago
@Abhigyan reddy.
The units digit can be 1, 3, 7 or 9.
The units digit can be 1, 3, 7 or 9.
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