Each year for 4 years, a farmer increased the number of trees…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: This problem is testing us on exponential growth. The easiest way to navigate this problem is to set up a growth chart. We are …
Sixty percent of the members of a study group are women…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: This is a two-part probability question. We should first notice that since our answer choices are in decimal form, we can use a real …
The present ratio of students to teachers at a certain school…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: We are given that the ratio of students to teacher is 30 to 1. We can rewrite this using variable multipliers. students : teachers …
If a square mirror has a 20-inch diagonal, what is the…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: We are given that a square has a 20-inch diagonal, and we must solve for the perimeter of the square. This means we first …
The water from one outlet flowing at a constant rate can fill…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: This problem is called a combined work problem. In these problems we use the formula: Work (of machine 1) + Work (of machine 2) …
On a scale that measures the intensity of a certain phenomenon…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: To solve this problem we need to examine the information in the first sentence. We are told that “a reading of n + 1 …
Water consists of hydrogen and oxygen…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: We are given that the ratio of hydrogen to oxygen in water, by mass, is 2 : 16. Using our ratio multiplier we can …
In a certain city, 60% of the registered voters are democrats…
May 6, 2015
GMAT OFFICIAL GUIDE PS Solution: We are given that 60 percent of the voters are Democrats and the rest are Republicans. This means that 40 percent are Republicans. We …