Difficult Math Question #2

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Difficult Math Question #2

by 800guy » Sat Aug 26, 2006 8:28 am
OA coming after a few people responded..

The price of a bushel of corn is currently $3.20, and the price of a peck of wheat is $5.80. The price of corn is increasing at a constant rate of 5x cents per day while the price of wheat is decreasing at a constant rate of (square root of 2)(x) - x cents per day. What is the approximate price when a bushel of corn costs the same amount as a peck of wheat?
Source: — Problem Solving |

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by aim-wsc » Sat Aug 26, 2006 1:18 pm
everyday corn price is increasing by 5x. that means after 'd' no. of days it d hv increased by (d X 5x)

similarly, (d X (sqrt2 x-x)) (simplify it.)
would be the amount cut from rice.
make formula

d. 5x+ 320= 580-(d. x. (sqrt2-1))

solve it.
dx=48.51 to be precise.
put this value on any of side.
lets put it LHS.
320+(5 X 48.51) ok?
bring them on! i m hungry!!

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by aim-wsc » Sat Aug 26, 2006 8:23 pm
this 2nd prob was much tough...
had options been provided, it would hv much easy.

u didnt hv to calculate exact figure then.

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by 800guy » Mon Aug 28, 2006 7:25 pm
OA:

Soln: 320 + 5x = 580 - .41x; x = # of days after price is same;

solving for x; x is approximately 48, thus the required price is 320 + 5 * 48 = 560 cents = $5.6

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by malhotneha » Sun Jan 11, 2009 10:32 am
800guy wrote:OA:

Soln: 320 + 5x = 580 - .41x; x = # of days after price is same;

solving for x; x is approximately 48, thus the required price is 320 + 5 * 48 = 560 cents = $5.6

Thanks...but could you please tell me how you got .41x in your equation. :?:

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by Stuart@KaplanGMAT » Sun Jan 11, 2009 11:01 am
malhotneha wrote:
800guy wrote:OA:

Soln: 320 + 5x = 580 - .41x; x = # of days after price is same;

solving for x; x is approximately 48, thus the required price is 320 + 5 * 48 = 560 cents = $5.6

Thanks...but could you please tell me how you got .41x in your equation. :?:
root2 is approximately 1.41, so root2(x) - x = (1.41 - 1)x = .41x
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by badpit » Mon Feb 16, 2009 4:07 am
I think that this document, where the questions came from, is full of bullshits. You cannot give a GMAT question like this and expect that we will think x as unknown to be the # of days.