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If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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14 Mar 2016, 18:08
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If the tens digit of positive integers x, y are 6, how many values of the tens digit of 2(x+y) can be there? A. 2 B. 3 C. 4 D. 5 E. 6 * A solution will be posted in two days.
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Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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17 Mar 2016, 18:20
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If the tens digit of positive integers x, y are 6, how many values of the tens digit of 2(x+y) can be there? A. 2 B. 3 C. 4 D. 5 E. 6 > If X=y=60, 2(x+y)=240 is derived. If x=y=69, 2(x+y)=276 is derived, which makes 4,5,6,7 possible for the tens digit. Therefore, the answer is C.
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Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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17 Jul 2016, 05:16
Hi! did used a small layman method.. correct my approach (though crack down the answer correctly) lets fix 6 for x for y we have 1 .....9 = means 9 numbers 1+6 =7 2+6= 8 3+6= 9 4+6= 1 (10 but took 1 as for tens digit) 5+6 =1 (11... took 1 for tens digit) ... .. . so all 1 for tens digit hence same.
7,8,9,1 means 4 ... correct me . really interesting question.



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Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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22 Aug 2016, 02:22
I get 2 as ans.
If the sum of the units digits of X and Y is less than 9, then the tens digits of x+y is 2. When this sum is multiplied by the 2, the tens digit will become 4.
If the sum of the units digit of X and Y is more than 9, then the tens digit of x+y is 3, because maximum 1 can be carried over from units place and thus 6+1+6 will leave 3 in the tens place. 3*2 will leave 6 for 2(x+y).
Thus total 2 numbers in tens place for the operation 2(x+y)!!
please tell me where am i going wrong?



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Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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22 Aug 2016, 09:11
deeksha6 wrote: I get 2 as ans.
If the sum of the units digits of X and Y is less than 9, then the tens digits of x+y is 2. When this sum is multiplied by the 2, the tens digit will become 4.
If the sum of the units digit of X and Y is more than 9, then the tens digit of x+y is 3, because maximum 1 can be carried over from units place and thus 6+1+6 will leave 3 in the tens place. 3*2 will leave 6 for 2(x+y).
Thus total 2 numbers in tens place for the operation 2(x+y)!!
please tell me where am i going wrong? Hey you are missing something after multiplication that can be carry over.
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Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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23 Aug 2016, 01:54
sahil7389 wrote: deeksha6 wrote: I get 2 as ans.
If the sum of the units digits of X and Y is less than 9, then the tens digits of x+y is 2. When this sum is multiplied by the 2, the tens digit will become 4.
If the sum of the units digit of X and Y is more than 9, then the tens digit of x+y is 3, because maximum 1 can be carried over from units place and thus 6+1+6 will leave 3 in the tens place. 3*2 will leave 6 for 2(x+y).
Thus total 2 numbers in tens place for the operation 2(x+y)!!
please tell me where am i going wrong? Hey you are missing something after multiplication that can be carry over. Yes! Thank you for pointing that out



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Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]
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12 Feb 2018, 09:12
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MathRevolution wrote: If the tens digit of positive integers x, y are 6, how many values of the tens digit of 2(x+y) can be there? A. 2 B. 3 C. 4 D. 5 E. 6
* A solution will be posted in two days. Minimum value possible = 60+60=120*2=240 Maximum value possible = 69+69=138*2=276 Thus, all values between 4 and 7 inclusive  4,5,6 and 7  can be present as tense digit. Answer should be C
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Re: If the tens digit of positive integers x, y are 6, how many values of
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