Number Properties

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Number Properties

by N:Dure » Mon Jan 03, 2011 5:50 am
X is a two-digit number. The digits of X differ by 6 and their squares differ by 60.

Which is bigger?

A) X
B) 60


When you solve this, you'll get that the first no. is 8 and 2nd is 2, making the number 82. The OA however says it can be 82 or 28...is he treating 6 as an absolute value? cause 2-8 isn't = 6

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by Anurag@Gurome » Mon Jan 03, 2011 6:13 am
N:Dure wrote:When you solve this, you'll get that the first no. is 8 and 2nd is 2, making the number 82. The OA however says it can be 82 or 28...is he treating 6 as an absolute value? cause 2-8 isn't = 6
The problem says they "differ" by...
Difference between two number is equal to (larger - smaller) and thus always positive.
For example in this case, difference of 2 and 8 is same as difference between 8 and 2 and equal to 6. Thus whenever you have to represent the difference between two number x and y as an equation, you must write their difference as |x - y| as you don't which one is larger.
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by Balrog1978 » Mon Jan 03, 2011 8:51 am
So the Number could be 82 and 28 thus we don't know which in this case?