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)}?
2
3
5
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 5 of 13.

Venugopal said:   1 decade ago
Thanks. I understood the answer. But when the end no is 3. E.g. (2463) power 323.

Then how to solve explain this?

Vamsi krishna said:   6 years ago
First, we can add the last unit digits without considering powers.
4+5+1=10.

The above 10 last digits was zero.

Dibakara nayajk said:   1 decade ago
4* 4 = 16 - 6 ->2
16 *4 = 84 - 4 ->3

5 * n = ..5
1 8 n = 1
(6 /4 ) * 5 * 1 = ......0


so ans is 0;

Reza Khan(BD) said:   6 years ago
We know,

(4)^n=unit digit 4; if n=even number.
Cause 4^(1/3/5) = unit digit 4.
So, 4^1793 gives unit digit 4.

RAGH said:   9 years ago
Find the product of the first 8 terms of a 15 number sequence whose 1st, 3rd, 5th numbers are 60, 45 and 30?

Aruna said:   1 decade ago
Unit digit means last digit..
5^(anything) is ending with 5..

So for our convenience it s considered as 5.

Emela said:   1 decade ago
How can you divide 1793 simply by 4 and write that remainder? is it applicable for any number like 6^, 7^.

Nanditha said:   10 years ago
Answer for 2463^323 may be after considering the cyclicity of 3 i.e., 4 we may get 3 as the answer.

Don said:   1 decade ago
What happend? jus can't understand. Hemanth method is good but what if it is 622^ () then wat?

Varun said:   1 decade ago
What will be the remainder if 2^856 is divided by 9?

Can any one mail me shortest trick?


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