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If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:04
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If both A and B are 2digit positive even numbers, what is the value of A? (1) Ratio of A to B is 1:9 (2) BA=80 New question!!!..
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:22
Update: My analysis for this question is wrong. Please check out other explanations.To find the value of A A and B are 2digit even numbers Statement 1Ratio of A to B is 1:9 => \(\frac{A}{B} = \frac{x}{9x}\) => A can be 10 and B can be 90 satisfying that A and B are both even numbers and \(\frac{A}{B} = \frac{1}{9}\) => A can be 20 and B can be 180 satisfying that A and B are both even numbers and \(\frac{A}{B} = \frac{1}{9}\) Statement 1 is not sufficientStatement 2BA=80 => A can be 10 and B can be 90 satisfying that A and B are both even numbers => A can be 20 and B can be 100 satisfying that A and B are both even numbers Statement 2 is not sufficientCombining statements 1 and 2A = x and B = 9x and AB = 9x  x = 8x = 80 => x = 10 => A = x = 10 and B = 9x = 90 Statements 1 and 2 together are sufficientHence option C
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:26
workout wrote: Hence option C workout, A cannot be 2 as it is 2digit number. you may have to relook in the statement I Given info A and B are 2digit even numebrs 1) A:B=1:9 so if A is 10, B is 90 if A is 11, B is 99 and when A = 12, B=12*9=108.... NOT possible as B is 2digit number So A can be 10 or 11, but A is EVEN, so A=10 suff 2) BA=80 A can be 10,12,14,16 or 18 insuff A
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:34
chetan2u wrote: workout, A cannot be 2 as it is 2digit number. you may have to relook in the statement I Thanks chetan2u for catching that. Careless mistake on my part. I have updated the example cases.
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:37
workout wrote: chetan2u wrote: workout, A cannot be 2 as it is 2digit number. you may have to relook in the statement I Thanks chetan2u for catching that. Careless mistake on my part. I have updated the example cases. another careless mistake.. B cannot be 3digit number
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:38
chetan2u wrote: If both A and B are 2digit even numbers, what is the value of A? (1) Ratio of A to B is 1:9 (2) BA=80
New question!!!.. OA: A Given:A and B are 2digit even numbers, what is the value of A (1) Ratio of A to B is 1:9 Take A as 10 (lowest 2 digit even number) then B = 90 Now take A as 12 , then B =108 which is not possible as per question stem So A= 10 Statement 1 alone is sufficient (2) BA=80 Let us take B= 98(greatest/highest twodigit even number) then A =18 Taking B=96, A =16 Similarly,B can be 98,96,94,92 or 90, and A can be 18,16,14,12 or 10 There is no unique value of A as per statement 2. So Statement 2 alone is not sufficient



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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:38
chetan2u wrote: If both A and B are 2digit even numbers, what is the value of A? (1) Ratio of A to B is 1:9 (2) BA=80
New question!!!.. Is it A? Given: A : B = 1 : 9 Also given: A & B are both 2digit even numbers. So, the smallest 2digit even number is 10, which would make B = 90. The next even number is 12 but that would make B = 108. So, Statement 1 is sufficient to uniquely identify the value of A. Statement B is insufficient because there is more than one possible value of A that would satisfy the condition (10,90; 12,92; ... 18,98)



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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:39
chetan2u wrote: If both A and B are 2digit even numbers, what is the value of A? (1) Ratio of A to B is 1:9 (2) BA=80
New question!!!.. 1. Ratio of A to B is 1:9Since both A and B are 2 digit even numbers with ratio 1:9, If A = 10(first twodigit even number) B = 90 Let A = 12, then B = 108(which is a 3digit number) We are able to uniquely determine the value of A (Sufficient)2. B  A = 80Since the difference of B and A is 80, If B = 90, then A = 10 Similarly, if B = 92, then A = 12 We are not able to determine an unique value of A (Insufficient)(Option A)
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:46
chetan2u wrote: workout wrote: chetan2u wrote: workout, A cannot be 2 as it is 2digit number. you may have to relook in the statement I Thanks chetan2u for catching that. Careless mistake on my part. I have updated the example cases. another careless mistake.. B cannot be 3digit number Looks like I need more caffeine in. Thanks for these wonderful questions. I am just gonna keep my post the same (no editing) so that others can learn from my mistake.
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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:47
If both A and B are 2digit even numbers, what is the value of A? (1) Ratio of A to B is 1:9 (2) BA=80 Given : A & B are 2 digit even number , so Smallest/Largest value each can take is 10/98. To Find A = ? Statement (1) A/B = 1/9 Let me assume A to be smallest value, i.e A = 10 10/B = 1/9 B = 9*10 = 90 Let me assume A to be second smallest even number, i.e A = 12 12/B = 1/9 B = 12*9 B = 108 Discarded, as B is a 2 digit even number !!! So we have unique values of A & B , 10 & 90 respectively . Statement (1) is sufficient. Statement(2) : BA=80 A can take values from : 10 to 18 B can take values from : 90 to 98 90  10 = 80 , 92  12 = 80 , etc etc So no unique values for A & B pair, hence Statement (2) is not sufficient. Correct answer: (A)pls give kudos if you liked the explanation



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Re: If both A and B are 2digit even numbers, what is the value of A?
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27 Jul 2018, 22:56
chetan2u wrote: If both A and B are 2digit even numbers, what is the value of A? (1) Ratio of A to B is 1:9 (2) BA=80
New question!!!.. Let \(A = xy, B = cd\) Statement I: \(cd = 9*xy\), which means \(xy = 10/12\).... Sufficient. Statement II: \(10(cx) + (dy) = 80\), which means \(cx = 8\) and \(d= y.\) c = 9, x = 1. Again, Insufficient as xy = 10/12 & cd = 90/92. Hence, A.
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Re: If both A and B are 2digit even numbers, what is the value of A?
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29 Jul 2018, 05:37
pushpitkc chetan2uBut why? 1/9 could also be 10/90 in which case the value of A would be 10 Or it could be 10/90 then the value of A could be 10 So I think therefore answer is C because nowhere it is mentioned that both are positive even two digit no.s



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Re: If both A and B are 2digit even numbers, what is the value of A?
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29 Jul 2018, 06:09
BigUD94 wrote: pushpitkc chetan2uBut why? 1/9 could also be 10/90 in which case the value of A would be 10 Or it could be 10/90 then the value of A could be 10 So I think therefore answer is C because nowhere it is mentioned that both are positive even two digit no.s Hi... Yes in most cases I have seen on OG they mention that positive 2digit integers or 2digit positive integers. But once in a while they have skipped it too. But I am yet to see a question which meant a 2digit number to mean a negative number too.. If they have wanted to create a trap, they generally write X is an integer with 2 digits.. Also if I write a ratio as 1:9 it means the second is 9 times more than the first but 90 is not exactly 9 times more than 10, it is 9times lesser.. But would follow what OG follows most of the time, so editing and thank you..
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Re: If both A and B are 2digit even numbers, what is the value of A?
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29 Jul 2018, 08:51
A and B are two 2digit positive even numbers. Statement 1 A/B= 1/9 There are two options are here. 10/90 or 11/99 as both numbers are even so 10/90 is ok. Sufficient.
take statement 2 BA= 10 9010= 80 9282= 80 Not sufficient.
A is answer.




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