Hi Amit,
When it comes to TESTing VALUES/Picking Numbers, there's a bit more strategy to choosing your values than just 'randomly' doing so. Many prompts in the Quant section can be solved with this approach (or you can use that approach to define a hidden pattern in the question and then use general math to answer the question). Often, the design of the prompt (and/or the answer choices) will provide a hint as to what value(s) will make the work easy to deal with. For example, when a question deals with percents, it's often easiest to TEST the number 100.
In this prompt, the Roman Numerals themselves serve as something of a guide. Given that X > Y^2 > Z^4 and Roman Numeral 1 is X>Y>Z, can you come up with a simple example that fits both inequalities? Remember to keep things simple (eg. making Z=0 in this situation cuts the 'work' down considerably).
Learning the subtleties of this strategy takes time and effort, so you can't just boil it down to a 'list' that you'll memorize. To become efficient at all of this, you have to practice again and again.
GMAT assassins aren't born, they're made,
Rich
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If x > y2 > z4
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I wouldn't say that list covers *every* possibility, but it should see you through most inequalities that respond well to plugging in.gmat_for_life wrote:Hello Rich and Matt,
I do face issues while trying to plug in the numbers because I go for random plugging of numbers. Could you please let me know if the list of number sets mentioned in the post below can be applied to all types of inequality questions?
Regards,
Amit
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I would focus on refreshing on number theory - particularly, understanding things like scientific notation and how fractions behave when raised to an exponent. Should be helpful in coming up with quick and easy values to test.gmat_for_life wrote:Hello Rich and Matt,
I do face issues while trying to plug in the numbers because I go for random plugging of numbers. Could you please let me know if the list of number sets mentioned in the post below can be applied to all types of inequality questions?
Regards,
Amit
For (I), I would set x = 10^10, y = 10^3, and z = 10. Then x = 10^10, y^2 = (10^3)^2 = 10^6, and z^4 = 10^4. So we have proven it can be true without doing any real calculation, other than understanding how exponents work.
For (II), I'd pick three fractions. Pure fractions always get smaller when raised to an exponent. Set x = 1/3, y = 1/2, and z = 2/3. Then x = 1/3 > y^2 = 1/4 > z^4 = 16/81.
And (III) logically follows from (I) & (II) - simply use x from (I) and y and z from (II) as before.
Therefore, all of (I), (II), and (III) could be true.
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