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When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 08:42
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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 10:24
Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined since x is positive and 20 is multiple of 5 , we can divide 8 by 5 to get 3 remainder Ans B



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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 10:42
Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined There's a nice rule that say, " If N divided by D equals Q with remainder R, then N = DQ + R" For example, since 17 divided by 5 equals 3 with remainder 2, then we can write 17 = (5)(3) + 2 Likewise, since 53 divided by 10 equals 5 with remainder 3, then we can write 53 = (10)(5) + 3 In this case, we aren't told how many times 20 divides into x, but this isn't a problem. Let's just say that 20 divides into x k times. In other words, x divided by 20 equals k with remainder 8Applying the above rule, we can then say: x = 20k + 8 for some positive integer k What is the remainder when x is divided by 5? We know that: x = 20k + 8 Rewrite as: x = 20k + 5 + 3 And the factor to get: x = 5(4k + 1) + 3So, we can see that x is 3 greater than some multiple of 5This tells us that, if we divide x by 5, the remainder will be 3Answer: B Cheers, Brent
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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 10:43
Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined Quote: When positive integer x is divided by 20, the remainder is 8. Lest possible value of x = 28. Quote: remainder when x is divided by 5 Is, 3 Hence, correct aswer must be (B) 3
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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 10:46
Abhishek009 wrote: Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined Quote: When positive integer x is divided by 20, the remainder is 8. Lest possible value of x = 28. Quote: remainder when x is divided by 5 Is, 3 Hence, correct aswer must be (B) 3Isn't least possible value 8 when quotient is 0



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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 10:57
Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined Another approach: When it comes to remainders, we have a nice rule that says: If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, R+3D,. . . etc. For example, if k divided by 5 leaves a remainder of 1, then the possible values of k are: 1, 1+5, 1+(2)(5), 1+(3)(5), 1+(4)(5), . . . etc. When positive integer x is divided by 20, the remainder is 8. So, the possible values of x are: 8, 28, 48, 68, 88,... Let's test a few values 8 divided by 5 equals 1 with remainder 328 divided by 5 equals 5 with remainder 348 divided by 5 equals 9 with remainder 368 divided by 5 equals 13 with remainder 388 divided by 5 equals 17 with remainder 3. . . It certainly LOOKS like the remainder will always be 3Answer: B Cheers, Brent
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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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10 Feb 2017, 22:50
Abhishek009 wrote: Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined Quote: When positive integer x is divided by 20, the remainder is 8. Lest possible value of x = 28. Quote: remainder when x is divided by 5 Is, 3 Hence, correct aswer must be (B) 3To add to this least possible value of x is 8 not 28. Sent from my iPad using GMAT Club Forum mobile app



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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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11 Feb 2017, 01:19
warriorguy wrote: Abhishek009 wrote: Bunuel wrote: When positive integer x is divided by 20, the remainder is 8. What is the remainder when x is divided by 5?
A. 1 B. 3 C. 5 D. 8 E. Cannot be determined Quote: When positive integer x is divided by 20, the remainder is 8. Lest possible value of x = 28. Quote: remainder when x is divided by 5 Is, 3 Hence, correct aswer must be (B) 3Isn't least possible value 8 when quotient is 0 You are correct. x=20q +8 When q=0......x=8 when divided by 5 the reminder is 3.



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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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11 Feb 2017, 02:28
awdxzs wrote: To add to this least possible value of x is 8 not 28. Admit that its 8...
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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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11 Feb 2017, 02:40
When x is divided by 20, the remainder is 8. therefore x is of the form 20k+8 where k is an integer.
so x=20k+8=20k+5+3=5(4k+1)+3
When x is divided by 5, the component 5(4k+1) is divisible by 5. Hence remainder when x is divided by 5 = remainder(3/5) = 3.
Answer B



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Re: When positive integer x is divided by 20, the remainder is 8. What is [#permalink]
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19 Feb 2017, 22:48
check least possible value for which x results in remainder 8 28/20 results in remainder 8 then divide 28/5 the result is 3 choice B **Experts Please respond as I am a beginner
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