Quantitative Comparison in GRE

Numbers enable us to comprehend and visualize the relative size and volume of various objects. Widespread innumeracy among masses these days is blamed for an increasing number of wrong decisions made by people. Decision making at all levels is heavily dependent on understanding the relative magnitude of objects one is talking about. Researchers have done interesting social experiments exposing the human tendency to simplify information coming to us and in many cases, this simplification leads to erroneous decisions made.
One such example is given by Chip Heath in his book “Made to Stick”, which compares the seemingly big amount of aid to Africa with something we can all easily understand. Most observers believe that a lot of money is given by the United States as financial aid to African countries, but in reality, it is very low when compared to what other countries give and also in absolute value terms.
“Polls suggest that most Americans think the federal government spends about 10 to 15 percent of its budget on foreign aid. The truth is that we spend less than 1 percent, the lowest of any industrialized nation. All of sub-Saharan Africa receives just over $1 billion in economic aid. If everyone in the United States gave up one soft drink a month, we could double our current aid to Africa.”
— Chip Heath in “Made to Stick” Pg 78
Similarly, in their famous book, Freakonomics, authors Steven Levitt and Stephen Dubner point out the weightage we as common humans give to certain objects. Most people when asked whether they would send their kids to a neighbor’s home knowing that they have a gun or to someone who has a swimming pool. As expected, most people would declare one with a swimming pool to be a safe one as compared to one with a gun, but statistics show that 100 times more children are killed by drowning in residential swimming pools than by guns.
In GRE Quantitative Comparison, the test takers are tested on their understanding of the relative magnitude of numbers. A billion, for example, is 1000 times bigger than a million, which in turn is 1000 times a thousand. Multiplying by a positive fraction makes a positive integer smaller whereas dividing by the same fraction will make it bigger.