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x and y are positive integers
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25 Dec 2019, 02:36
25 Dec 2019, 02:36
Expert Reply
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Question Stats:
80% (00:43) correct
20% (00:32) wrong based on 35 sessions
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\(x\) and \(y\) are positive integers
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation[/m]
Quantity A |
Quantity B |
The unit digit of \(2^x5^y\) |
The unit digit of \(2^x6^y\) |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation[/m]
Re: x and y are positive integers
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25 Dec 2019, 23:57
25 Dec 2019, 23:57
1
it is a question of units digits.
2 has a cyclically of 4.
2^1=2
2^2=4
2^3=8
2^4=16
5 always have unit digit of 5 and 6 will have 6 for every power.
next step is to multiply.in each case when we multiple unit digit of 6 with unit digit of 2 for different powers, the unit digit of 2^x2^y will be greater
2 has a cyclically of 4.
2^1=2
2^2=4
2^3=8
2^4=16
5 always have unit digit of 5 and 6 will have 6 for every power.
next step is to multiply.in each case when we multiple unit digit of 6 with unit digit of 2 for different powers, the unit digit of 2^x2^y will be greater
Re: x and y are positive integers
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26 Dec 2019, 02:20
26 Dec 2019, 02:20
1
5^(any positive integer) = 5
6^(any positive integer) = 6
Now any power of 2*5 will have a unit digit of 0.
whereas 2*6 = 12, 4*6 = 24, 8*6 = 36 16*6 = 96
So, in case B is greater.
OA, B
6^(any positive integer) = 6
Now any power of 2*5 will have a unit digit of 0.
whereas 2*6 = 12, 4*6 = 24, 8*6 = 36 16*6 = 96
So, in case B is greater.
OA, B
Carcass wrote:
\(x\) and \(y\) are positive integers
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation[/m]
Quantity A |
Quantity B |
The unit digit of \(2^x5^y\) |
The unit digit of \(2^x6^y\) |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation[/m]
