What is the value of the two-digit positive integer n?
1- The sum of the digits in n is 12
2- If the digits in a are reversed, the value of the number formed is 36 more than the value of n.
The answer is C)Together. But why not B ? Why the statement 2- alone is not enough ? Can we found other numbers than 84 and 48 ?
Thanks
The value of two digit integer
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How about 37 and 73?yass20015 wrote:What is the value of the two-digit positive integer n?
1- The sum of the digits in n is 12
2- If the digits in a are reversed, the value of the number formed is 36 more than the value of n.
The answer is C)Together. But why not B ? Why the statement 2- alone is not enough ? Can we found other numbers than 84 and 48 ?
Thanks
Or 26 and 62?
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Brent
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In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem.
Remember equal number of variables and equations ensures a solution.
=> Since we have 2 variables (units digit and tens digit) in the original condition, we need 2 equations to solve the problem and thus the answer is C. (1) 1 equation, (2) 1 equation
=> 2) is not the answer because the number of n is NOT unique, NOT sufficient,
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Remember equal number of variables and equations ensures a solution.
=> Since we have 2 variables (units digit and tens digit) in the original condition, we need 2 equations to solve the problem and thus the answer is C. (1) 1 equation, (2) 1 equation
=> 2) is not the answer because the number of n is NOT unique, NOT sufficient,
If you know our own innovative logics to find the answer, you don't need to actually solve the problem.
www.mathrevolution.com
- The one-and-only World's First Variable Approach for DS and IVY Approach for PS that allow anyone to easily solve GMAT math questions.
- The easy-to-use solutions. Math skills are totally irrelevant. Forget conventional ways of solving math questions.
- The most effective time management for GMAT math to date allowing you to solve 37 questions with 10 minutes to spare
- Hitting a score of 45 is very easy and points and 49-51 is also doable.
- Unlimited Access to over 120 free video lessons at https://www.mathrevolution.com/gmat/lesson
- Our advertising video at https://www.youtube.com/watch?v=R_Fki3_2vO8