What is the value of the units digit of 22^44?

Question

A. 8
B. 6
C. 5
D. 4
E. 2

broall · Answer

$22^{44}=22^{2 \times 22} = (22^2)^{2 \times 11}=((...4)^2)^{11}=(...6)^{11}=(...6)$

The answer is B

eddy8700 · Answer

answer is B

cyclicity of 2 is 4 i.e 2,4,8,6,2, 
so 2^44 =unit digit 6

mohshu · Answer

cyclicity of 2 is 4... hence the unit digit will be same as 2^44 = 6

ans 6

matthewsmith_89 · Answer

Last unit digit
2^1= 2
2^2 = 4
2^3 = 8
2^4 = 6
2^5 = 2
2^6 = 4
2^7 = 8
2^8 = 6

44 is a multiple of 4. Therefore the answer is B 6

Abhishek009 · Answer

Cyclicity of the digit 2 is 4 -

2^1 = 2
2^2 = 4
2^3 = 8
2^4 = 16

2^5 = 32

Now,  22^{44} = 22^{4*11}

Since,  2^4  has units digit as  6  , the units digit of  22^{44}  will have the units digit as  6  , answer must be (B)  6

JeffTargetTestPrep · Answer

Since we need to determine the units digit of 22^44, we really are determining the units digit of 2^44.

The pattern of units digits of 2 when raised to a positive integer exponent is:

2^1 = 2

2^2 = 4

2^3 = 8

2^4 = 6

2^5 = 2

We see that the pattern is 2-4-8-6. Furthermore, 2^4k, in which k is a positive integer, will always have a units digit of 6. From this we can see that 2^4 has a units digit of 6, as do 2^8 and 2^12. When 2 is raised to an exponent that is a multiple of 4, the units digit of the product will be 6.

Thus, the units digit of 2^44 is 6.

Answer: B

akadiyan · Answer

The power of 2’s comes in pattern 2,4,8,6. This pattern repeats in block of 4.

So in 22^44, 44th power ends in 6

Ans: B

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What is the value of the units digit of 22^44?

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What is the value of the units digit of 22^44?

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