Hello: I;m posting again as I think I posted in the wrong forum.
I encountered a question regarding GMAT symbolism which has me scratching my head a little. The question is:
~x=(x^2+1)/2 ; ~y=3y/2 for all integers x and y. If m=2, ~m is equal to which of the following:
A. 13/8
B. 3
C. 15/4
D. 5
E. 37/2
The answer is D.
for ~x, x is in a cirled and for ~y, y is in a box. For ~m, m is in a box and a circle.
Thanks!
GMAT symbolism
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- jayhawk2001
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If I understand the question correctly, we have to compute
~2 based on formula for ~y and then use the result in ~x
So, we have
~2 = 3*2/2 = 3
Using this in ~x, we have (3^2 + 1) / 2 = 5
If you have a snapshot (pictorial representation) of the question,
please send so that we can confirm
~2 based on formula for ~y and then use the result in ~x
So, we have
~2 = 3*2/2 = 3
Using this in ~x, we have (3^2 + 1) / 2 = 5
If you have a snapshot (pictorial representation) of the question,
please send so that we can confirm
Jay,
Sorry, call me thick, but if you put x as equal to 2, solve then sub in for y the equation does not calculate (following the same logic just solving for x first). I don't get it. How does one know when to solve for y first and then x or vice versa? I simply cannot follow your logic.
L.
Sorry, call me thick, but if you put x as equal to 2, solve then sub in for y the equation does not calculate (following the same logic just solving for x first). I don't get it. How does one know when to solve for y first and then x or vice versa? I simply cannot follow your logic.
L.
- ajith
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Let me re-phase the question to a more mathematical formLynn0423 wrote:Hello: I;m posting again as I think I posted in the wrong forum.
I encountered a question regarding GMAT symbolism which has me scratching my head a little. The question is:
~x=(x^2+1)/2 ; ~y=3y/2 for all integers x and y. If m=2, ~m is equal to which of the following:
A. 13/8
B. 3
C. 15/4
D. 5
E. 37/2
The answer is D.
for ~x, x is in a cirled and for ~y, y is in a box. For ~m, m is in a box and a circle.
Thanks!
f(x) = (x^2+1)/2
g(x) = 3*x/2
Now they are asking for f (g(2))
for this
g(2) = 2*3/2 =3
f(g(2) = f(3) = (3^2+1)/2 =10/2 =5
Always borrow money from a pessimist, he doesn't expect to be paid back.
- ajith
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That depends on whetherLynn0423 wrote:Jay,
How does one know when to solve for y first and then x or vice versa? I simply cannot follow your logic.
L.
a) 2 is in the circle enclosed by the box
b) 2 is in the box enclosed by circle
do the innermost operation first
I will explain in case of a
Do the operation curresponding to circle first because that is inner
Do the outer operation next on the result of first operation.
is it clear?
Always borrow money from a pessimist, he doesn't expect to be paid back.
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This one seems simple enough. m is in a circle in a square.
Thus you first have to perform the function of a circle and then the square
Function in a circle = (x^2+1)/2 ; for any integer x
Thus for m=2 it equals (2^2 + 1)/2 = 5/2
Now perform the function of a square
Function in a square = (3y/2)
= 3/2 * 5/2 = 15/4
Thus you first have to perform the function of a circle and then the square
Function in a circle = (x^2+1)/2 ; for any integer x
Thus for m=2 it equals (2^2 + 1)/2 = 5/2
Now perform the function of a square
Function in a square = (3y/2)
= 3/2 * 5/2 = 15/4