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The last digit in the number 252^56
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20 Apr 2018, 11:32
20 Apr 2018, 11:32
Expert Reply
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Question Stats:
96% (00:23) correct
3% (00:13) wrong based on 53 sessions
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Quantity A |
Quantity B |
The last digit in the number \(252^{56}\) |
The last digit in the number \(152^{56}\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Re: The last digit in the number 252^56
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10 Mar 2019, 12:46
10 Mar 2019, 12:46
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Bump for further discussion
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Re: The last digit in the number 252^56
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11 Mar 2019, 10:35
11 Mar 2019, 10:35
1
Carcass wrote:
Quantity A |
Quantity B |
The last digit in the number \(252^{56}\) |
The last digit in the number \(152^{56}\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Since we about the UNITS digits only, the other digits in the base are irrelevant.
Consider these examples:
2² = 4 (units digit = 4)
12² = 144 (units digit = 4)
22² = 484 (units digit = 4)
52² = 2,704 (units digit = 4)
112² = 12,544 (units digit = 4)
172² = 29,584 (units digit = 4)
3072² = 9,437,184 (units digit = 4)
etc
Likewise, since 252 and 152 have the same units digit, we know that the units digit of 252^56 = the units digit of 152^56
So, Quantity A = Quantity B
Answer: C
Cheers,
Brent
