word problem

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word problem

by konan » Wed Feb 24, 2016 6:30 am
Mark bought shares of a particular stock for a total value of $1000. Next day, the price of shares is reduced by 10%. With the same $1000, he could now buy 10 more shares. Which of the following is closest to the original price per share? please help me with this....
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by DavidG@VeritasPrep » Wed Feb 24, 2016 6:43 am
konan wrote:Mark bought shares of a particular stock for a total value of $1000. Next day, the price of shares is reduced by 10%. With the same $1000, he could now buy 10 more shares. Which of the following is closest to the original price per share? please help me with this....
Some answer choices would be helpful :)

Algebraically, we can call the initial price 'p' and the initial number of shares 'q.' So p*q = 1000, or p =1000/q

If the price is reduced by 10%, the new price would be .9p. If he can buy 10 more shares, he can now afford q + 10 shares. So (.9p)(q+10) = 1000; Simplifying, we get .9pq + 9p = 1000. If, using our initial equation we substitute 1000/q in place of p, we'll have:
.9q(1000/q) + 9p = 1000
900 + 9p = 1000
9p = 100
p = 100/9 = 11.11111

So... whichever answer choice is closest to 11.11 would be your answer.
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by [email protected] » Wed Feb 24, 2016 10:01 am
Hi All,

The full prompt, with the answer choices, is here:

Mark bought shares for a total value of $1000. Next day, the price of shares is reduced by 10%. With the same $1000, he could now buy 10 more shares. Which of the following is closest to the original price per share?

A. $10
B. $11
C. $12
D. $13
E. $14

Final Answer: B

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