Which of the following cannot be the outcome of raising an integer to

Question

Which of the following cannot be the outcome of raising an integer to the 4th power?

A. 65,610,000
B. 68,574,961
C. 62,356,782
D. 52,200,625
E. 37,015,056

VibhuAnurag · Accepted Answer

The answer is C.

Units digits of 4th powers of numbers ending in different digits:
0^4 = 0
1^4 = 1
2^4 = 6
3^4 = 1
4^4 = 6
5^4 = 5
6^4 = 6
7^4 = 1
8^4 = 6
9^4 = 1

Hence, it can be seen that none of our numbers end in 2.

Archit3110 · Answer

Two close options are B & C
But option B is divisible by 7, so a multiple of 7 can be its factor possible.. 
Option C is correct.

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uCS2020 · Answer

To solve this question what I did was

I knew that if an integer starts with 5 then all its powers will end with a 5 so we can eliminate D
And that if an integer starts with 0 then all its powers will end with a 0 so we can eliminate A
So then I thought of listing other number’s units digit and see their patterns like that of the first 2 examples

Digit ending with 1 = 1,1,1. This always ends in 1,so we can eliminate B
Digit ending with 2 = 2,4,8,6,2 Now,this seems to be changing unlike the others,but what I can see in the pattern is that an integer with units digit of 2 and I raise to the power of 4 I get the units digits as 6

Eliminate E

That leaves us with C ,so it should be the answer.

Answer = C

If you want to check further then just list the numbers from 0 - 9 and see the units digit of the power of four.

Posted from my mobile device

Argh123 · Answer

4th power means it’s a square term … and square term can not have 2, 3 , 7 , 8 as unit digit . Hence c is the only option .

bumpbot · Answer

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Which of the following cannot be the outcome of raising an integer to

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Which of the following cannot be the outcome of raising an integer to

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