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What is the remainder when 7^2 * 8^2 is divided by 6?
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06 Feb 2016, 13:16
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What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5 Source: Gmat Math Bible
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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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06 Feb 2016, 13:28
BrainLab wrote: What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Source: Gmat Math Bible (7²)(8²) = ( 49)(64) = ( 48 + 1)(64) = ( 48)(64) + ( 1)(64) Since 48 is a multiple of 6, we can conclude that ( 48)(64) is a multiple of 6, so we get: = (some multiple of 6) + ( 1)(64) = (some multiple of 6) + 64 = (some multiple of 6) + 60 + 4 Since 60 is a multiple of 6, we can write: = (some multiple of 6) + (another multiple of 6) + 4 = (A MULTIPLE OF 6) + 4 So, when we divide the above by 6, we get a remainder of 4 Cheers, Brent
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What is the remainder when 7^2 * 8^2 is divided by 6?
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06 Feb 2016, 13:50
\((48+1)(60+4)=48*60+48*4+60+4\)=> All of them except 4 are divisible by 6, so the answer is 4 (D)
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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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06 Feb 2016, 13:35
BrainLab wrote: What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Source: Gmat Math Bible 7^2*8^2 = (56)^2 = (54+2)^2 = 54^2+2*2*54+2^2 = multiple of 6+multiple of 6 + 4 and this will give you a remainder of 4. D is the correct answer. Hope this helps.



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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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07 Feb 2016, 03:21
BrainLab wrote: What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Source: Gmat Math Bible a method different from above could be.. \(7^2 * 8^2\)= (6+1)^2*(6+2)^2.. (6+1)^2 will leave 1 as remainder and (6+2)^2 will leave 4 as remainder.. so overall remainder=1*4=4 D
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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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07 Feb 2016, 08:25
BrainLab wrote: What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Source: Gmat Math Bible the solution from chetan2u was mind blowing and most simplifying. However I have a remainder rule I know. "Multiply the remainders of the dividends and divide the product by the divisor" 49/6 is remainder 1. 64/6 is remainder 4. Therefore 4 * 1 equals 4. 4/6 is 0 remainder 4. Answer is D you know this rule, you do this math in 4 seconds.



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What is the remainder when 7^2 * 8^2 is divided by 6?
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25 Feb 2016, 03:14
BrainLab wrote: What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Source: Gmat Math Bible \(\frac{(49 * 64)}{6}\) gives remainer x 49 is remainder 1. 64 is remainder 4. 4*1 = 4. So x = 4 OR 7 is remainer 1. 8 is remainder 2 \(1^2 * 2^2 = 4\) D



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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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03 Dec 2016, 23:28



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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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04 Dec 2016, 00:12
BrainLab wrote: What is the remainder when \(7^2 * 8^2\) is divided by 6? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Source: Gmat Math Bible \(\frac{7^2}{6}\) = Remainder 1 \(\frac{8^2}{6}\) = Remainder 4 Thus, remainder of \(\frac{7^2 * 8^2}{6}\) will be 1*4 , ie 4 Hence remainder will be (D) 4
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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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07 Apr 2017, 04:24
I had come to an answer of 2.
This was my approach: 7^2*8^2 Simplify: 7*7*8*8 Then divide by 6: (7*7*8*8)/6 We get: (7*7*8*4)/3 We get 1568/3 Which gives a quotient of 522 and remainder of 2
What did I do incorrectly here?



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What is the remainder when 7^2 * 8^2 is divided by 6?
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27 Jun 2017, 15:06
Another way of looking at the problem:
(7^2 * 8^2)/6 = (56^2)/6
Now, since the remainder of 56/6 is 2 remainder of 56^2/6 will be 4.
Example: M/7 we get remainder r. What will be the remainder of M^2/7?
M = 7a+r. where a is a quotient and r is remainder.
M^2= (7a + r)(7a +r) = 49a^2 + 7ar + 7ar + r^2 M^2/7 = 49a^2/7 + 7ar/7 +7ar/7 + r^2 => Remainder is r^2.



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Re: What is the remainder when 7^2 * 8^2 is divided by 6?
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16 Jul 2018, 02:17
Why is it wrong to transform 49*64/6 into 49*32/3 (divide numerator and denominator by 2) Then remainder would be 2.. (48+1)(30+2)/3, 48 and 30 are multiples of 3, remainder=2 Why is it not possible to simplify the equation?
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Re: What is the remainder when 7^2 * 8^2 is divided by 6? &nbs
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