September 27, 2003

Comparisons

Quantitative Comparisons (or QC) comprise of half of the math section.

Remember the answer choices are always the same:
1. Column A is greater than Column B.
2. Column B is greater than Column A.
3. Both columns are equal.
4. The relationship between the columns cannot be determined.

Here are some interesting ones:

  Column A    Column B
1. The average (arithmetic mean) of 100, 101, 102.    The average (arithmetic mean) of 100, 101, 102.
Answer:
Choice 3 - Both columns are equal.

Here's another that is similar, but different:
 
2. The average (arithmetic mean) of 100, 101, 103.    The average (arithmetic mean) of 100, 101, 103.
Answer:
Choice 1 - Column A is greater than Column B.

A and B are points on the circumference of a circle. The length of chord AB is 15.
3. Circumference of the circle.    12 Pi.
Answer:
Choice 1 - Column A is greater than Column B. Since we know the length of the chord is 15, we know that the diameter of the circle is at least 15. The diameter is always the longest chord in a circle. So, the diameter of the circle is 15 or greater.

The product of two integers is 10.
4. The average (arithmetic mean) of the integers.    3
Answer:
Choice 4 - The relationship between the columns cannot be determined. First you man think, {2, 5} and {1, 10} make 10. However, since we're dealing with products, negative numbers can be too {-2, -5} and {-1, -10}. The products of these 4 sets of numbers is 10. But the average isn't always greater than 3.
Posted by oneray at September 27, 2003 7:21 AM