QC question

[anupinkm5]

help me. i cannot solve this question. please let me know how you solved it.

v& = 2v-1

quantity a : (V&)&
quantity b : 4v

[n00bpron00bpron00b]

v& = 2v-1 (given)

Lets simplify column A first

Col A : (v&)&

from above we know v& = 2v-1 ; so plugin this value inside the brackets

(v&)& will become (2v-1)&

Now,

If you notice (2v-1)& is of the same type as "v&" ; instead of "v" we have "2v-1"

Just plugin this value into the equation

(2v-1)& = 2(2v-1)-1

=> 4v-2-1
=> 4v-3

Now that we have both Col A and Col B values in terms of the same variable we can compare

Col A : 4v-3
Col B : 4v

Subtracting 4v from both columns

Col A : -3
Col B : 0

B is greater

[tommywallach]

Great explanation!

Just to be clear Anu, this is a function question presented in the form of a made up symbol. The GRE likes to do this. In other words, the ampersand (&) does not have any inherent mathematical meaning; they're simply PRETENDING it has a mathematical meaning. If it helps you, whenever they do this, you can translate things into a standard function presentation.

f(x) = 2x - 1

Col A: f(f(x))

Col B: 4x

This might make it easier to understand. Good luck!

-t

[anupinkm5]

thank you for helping me :)

[tommywallach]

Glad to do it!

-t

[danc]

Awesome.

[danc]

Awesome.

[anupinkm5]

:)

[tommywallach]

: ))