Alexmsi wrote:
@Bunuel:
I don't understand your approach for the first argument:
2x-1=odd
If the result muss be odd, so x must be even. It will be even if x is 2 or greater than 2. If x is odd the result won't be odd. If I say x = 1 so the result will be Zero. But Zero is neither even nor odd. So the satetement is sufficient ?
Several things:
1.
2x-1=odd -->
2x=odd+1=odd+odd=even --> so
2x=even -->
x=\frac{even}{2}=integer. Hence
2x-1=odd just means that
x is an integer (it can be even as well as odd).
2. If
x=1the result wont be zero, it'l be 1, so odd:
2*1-1=2-1=1=odd.
3.
Zero is an even integer. Zero is nether positive nor negative, but zero is definitely an even number.
An even number is an
integer that is "evenly divisible" by 2, i.e., divisible by 2 without a remainder and as zero is evenly divisible by 2 then it must be even (in fact zero is divisible by every integer except zero itself).
Or in another way: an even number is an
integer of the form
n=2k, where
k is an integer. So for
k=0 -->
n=2*0=0.
Hope it's clear.
_________________
PLEASE READ AND FOLLOW: 11 Rules for Posting!!!
RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory
COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. NEW!!!
DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set. NEW!!!
What are GMAT Club Tests?
25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
close
17% (01:19) correct
