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 2 of 13.
Abitha said:
5 years ago
Thanks for explaining @Seema.
Vishal Kishor Ramteke said:
5 years ago
Look here unit digit means the last digit.
Here we have - 6374*625*341=?
So, just see the last digit i.e 4,5,1 hence multiply them 4*5*1=20 now see the last digit i.e 0.
Therefore the answer is 0.
Here we have - 6374*625*341=?
So, just see the last digit i.e 4,5,1 hence multiply them 4*5*1=20 now see the last digit i.e 0.
Therefore the answer is 0.
(5)
Chetman said:
6 years ago
This can be done by this method too.
Just see the last number of the given number and the last number in the raise to find out the root.
Do the same for another two number.
Then you'll get three numbers after finding the root.
Then take the last numbers of these values and multiply them.
I checked it out for more other three example taken by myself and got it correct.
Just see the last number of the given number and the last number in the raise to find out the root.
Do the same for another two number.
Then you'll get three numbers after finding the root.
Then take the last numbers of these values and multiply them.
I checked it out for more other three example taken by myself and got it correct.
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.
(4)^n=unit digit 4; if n=even number.
Cause 4^(1/3/5) = unit digit 4.
So, 4^1793 gives unit digit 4.
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.
4+5+1=10.
The above 10 last digits was zero.
Kanimozhi said:
6 years ago
What is short trick of this sum? I can't understand easily.
Sumanth said:
6 years ago
You mentioned method is suitable for all the unit digit problems.
Prajna Samal said:
6 years ago
What is short trick of this sum? I can't understand easily.
Sandeep said:
6 years ago
The easiest way is in 1793 we take last two digits and 4 divide by means 93÷4 the remainder is 1 so in 6374 the unit digit is 4 so 4^1 is 4.
The answer is 4*5*1=20 unit digit is 0.
The answer is 4*5*1=20 unit digit is 0.
Harry said:
6 years ago
Thanks @Pooja.
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