Forget conventional ways of solving math questions. 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 independent equations ensures a solution.
Is x greater than 3.25?
(1) If x were rounded to the nearest thousandth, the result would be 3.254.
(2) If x were rounded to the nearest hundredth, the result would be 3.25.
When it comes to inequality, if range of que includes range of con, that con is sufficient.
In the original condition, there is 1 variable(x), which should match with the number of equations. So you need 1 equation. However, for 1) 1 equation, for 2) 1 equation, which is likely to make D the answer.
For 1), in 3.2535<=x<3.2545, the range of que includes the range of con, which is sufficient.
For 2), in 3.245<=x<3.255, the range of que doesn’t include the range of con, which is not sufficient.
Thus, A is the answer.
For cases where we need 1 more equation, such as original conditions with “1 variable”, or “2 variables and 1 equation”, or “3 variables and 2 equations”, we have 1 equation each in both 1) and 2). Therefore, there is 59 % chance that D is the answer, while A or B has 38% chance and C or E has 3% chance. Since D is most likely to be the answer using 1) and 2) separately according to DS definition. Obviously there may be cases where the answer is A, B, C or E.
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