by RonPurewal Wed Dec 24, 2008 7:13 am
also, if you're planning on picking up 5-10 additional points on the quant, you can be fairly sure that you won't be able to get all those points from learning "textbook" approaches to problems (unless you are severely deficient in one or more areas of basic knowledge, but, given your original mark of q40, that's extremely unlikely to be true).
instead, you've got to be flexible with your approach to quant problems, and START IMMEDIATELY ON SECONDARY PROBLEM-SOLVING METHODS for any problem on which you don't have a primary approach RIGHT AWAY.
"secondary methods" include number plugging, estimation, and other processes of elimination.
if you have SERIOUS issues with banging your head against the proverbial wall of trying to find a primary method, then consider using the following hierarchy to solve quant problems.
PROBLEM SOLVING:
1. can i find a "textbook method" to solve the problem?
- i.e., can i find an 'opener' that might be in an answer key, etc.?
IF NOT,
2. can i "plug in numbers"?
- note that there are two kinds of "plugging in numbers" for problem solving:
(a) plugging in YOUR OWN numbers, and working through the problem in the normal direction with your numbers instead of variables (VIC style problems),
(b) plugging in the ANSWER CHOICES and working the problem backwards (used if the answer choices are numbers and there's a decently easy path "backwards" through the problem).
IF NOT,
3. can i estimate, or perform process of elimination in any other way?
- if the answer choices are NUMBERS and there's a decent spread - i.e., not all of the answer choices are extremely close together - then you may be able to eliminate answers based on estimation. this goes especially for geometry problems, which have DIAGRAMS and are therefore easier to estimate, but it goes for all sorts of other problems as well.
IF NOT,
4. guess
- if you get to this point, DO NOT DELIBERATE - just guess. remember that any random guess is as good as any other random guess. if you're an extreme "deliberator", then, as weird as it may sound, you may want to have an actual method for random guessing. this could be as simple as "pick the first one of the remaining choices", but anything you can do to prevent staring at the problem is good.
DATA SUFFICIENCY:
1. can i find a "textbook method" to solve the problem?
- i.e., can i find an 'opener' that might be in an answer key, etc.?
IF NOT,
2. can i "plug in numbers"?
- note that NUMBER PLUGGING WORKS DIFFERENTLY FOR DATA SUFFICIENCY. with problem solving, all you have to do is plug in one set of numbers (VICs) or plug in one answer choice at a time (working backwards). with data sufficiency, though, you have to plug in MULTIPLE numbers or sets of numbers, with the goal being to TRY FOR 'INSUFFICIENT'.
in other words, you should try multiple values, with your goal being to get both a 'yes' and a 'no' (if it's a yes/no question) or two different values (if it's a value question).
if it's a number properties problem, you should make sure that you figure out the TYPES of numbers being tested, and plug in accordingly. for instance, if the problem involves absolute values, then it's likely that you'll have to plug in both positive and negative numbers.
IF NOT,
3. can i use the "easy statement", or perform process of elimination in any other way?
- always use the "easy statement" first, if there is one, and choose the grid (ad/bce or bd/ace) accordingly.
ironically, the hardest problems commonly have one very "easy" statement out of the two (such as a statement that doesn't contain one of the relevant variables).
IF NOT,
4. guess
- if you get to this point, DO NOT DELIBERATE - just guess. remember that any random guess is as good as any other random guess. if you're an extreme "deliberator", then, as weird as it may sound, you may want to have an actual method for random guessing. this could be as simple as "pick the first one of the remaining choices", but anything you can do to prevent staring at the problem is good.
never deliberate for more than 3 seconds without some sort of progress.