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 9 of 13.

Rajkumar said:   1 decade ago
How unit digit of (6374)^1793 is 4?

Please explain.

Raja shekhar said:   1 decade ago
What is unit digit? please explain anybody.

Vasundhara .G said:   1 decade ago
how can you make XI (11) as nine (9) just using a single line using only once
you must not replace or erase any line ...just draw a line any where to make it give nine

Nil said:   1 decade ago
@Satchi Mishra.

You are wrong. Not applicable to few no.s like 2^9.
2^9 = 512. unit digit 2.

By your method:

9/5=1, remainder 4.
2^4= 16. unit digit 6.

Not matches the case.

Ananya said:   1 decade ago
If the unit digit of (x-1)^2 is 5 and (x+1)^2 is 9 then determine the units of x^2?

Kishore said:   1 decade ago
For finding total result is there any logic? could you please explain?

Dr R Vasudevan said:   1 decade ago
For a number ending in 4 ( like 6534) any odd power will have unit digit 4 and Even power unit digit 6 ( 1731 is odd and hence 6534 6 1731 will have unit digit 4.

For a number ending in 5 ( like 625 ) any odd or even power , unit digit will result in 5

For a number ending in 1 ( like 341 ) any odd or even power , unit digit will result in 1

4*5*1 = 20 - Unit digit 0.

Ramya said:   1 decade ago
Its so simple,

Unit digit of 6374 is 4
Unit digit of 625 is 5
Unit digit of 341 is 1
Just multiply 4*5*1=20
So unit digit of 20 is 0

Answer is 0.

Abhishek said:   1 decade ago
Hemant method is very good..
Thx

Deepi said:   1 decade ago
Thanks to seema and jhansi.


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