Data comparison: Concepts & Tricks

Data Comparison questions test your knowledge of basic math facts and skills along with reasoning, analytical and problem solving abilities to solve questions. In each Data Comparison question, instead of solving for a particular value, you need to compare two quantities. At the outset, the Data Comparison question appears really difficult because of its unfamiliar format. However, if a person practices them well, they are quicker and easier to solve than the other type of math questions.
In each question, you see two mathematical expressions. They are boxed, one in Column A and the other in Column B. Your job is to compare them. Some questions include additional information about one or both quantities. This information is centered, unboxed and essential to make the comparison.
Directions: Each Data Comparison question consists of two quantities; one in column A and another is column B.
You have to find the column in which the data is higher. (Using your knowledge of mathematics and the given data), choose an option:
  1. If the quantity in column A is higher
  2. If the quantity in column B is higher
  3. If the two quantities are equal
  4. If the relationship cannot be established.
Points to Remember: Choice (A), (B) and (C) all represent definite relationship between the quantities in column A and column B. But choice (D) represents a relationship that cannot be determined. Here are two points to remember about choice (D) that will help you know when to pick it.
  1. Choice (D) is incorrect if both the columns contain only numbers.
  2. Choice (D) is correct if you can demonstrate two different relationships between the columns.
Data Comparison: Sample Question
Question: R, S and T are 3 consecutive odd integers.
Column A
Column B
R + S + 1
S + T – 1
Solution: Let R = 1, then S = 3, T = 5
Column A= R + S + 1 = 1 + 3 + 1 = 5.
Column B = S + T – 1 = 3 + 5 – 1 = 7.
Column B is Greater.
But let R = -1, then S = -3, T = - 5
Column A = R + S + 1 = -1 – 3 + 1 = -3.
Column B = S + T – 1 = -3 – 5 – 1 = -9.
Now, column A is greater.
So, answer is option (D).