I am having some problems with the follwing question and would really appreciate some help.
If all apples at a certain grocery store are equally priced, all all pears at the grocery store are equally priced, what is the price of a pear?
(1) Eight pears cost eighty cents more than eight apples
(2) Ten apples cost twenty cents more than eight pears
I think that it should be C), but I'm struggeling with the calculation. Please help.
DS problem - please help
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Target question: What is the price of one pear?mArikIo wrote:I am having some problems with the follwing question and would really appreciate some help.
If all apples at a certain grocery store are equally priced, all all pears at the grocery store are equally priced, what is the price of a pear?
(1) Eight pears cost eighty cents more than eight apples
(2) Ten apples cost twenty cents more than eight pears
Let P = price of 1 pear
Let A = price of 1 apple
We want to find the value of P.
Statement 1: Eight pears cost eighty cents more than eight apples
So, we can write: 8P - 8A = 80
Since we cannot solve this equation for P, statement 1 is NOT SUFFICIENT
Statement 2: Ten apples cost twenty cents more than eight pears
So, we can write: 10A - 8P = 20
Since we cannot solve this equation for P, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined:
We know that 8P - 8A = 80 and 10A - 8P = 20
Since we now have two different linear equations involving A and P, so we could solve this system for P, so the combined statements are SUFFICIENT
Answer = C
Aside: For those of you who wish to solve this system, take . . .
8P - 8A = 80
10A - 8P = 20
Rearrange the second equation . . .
8P - 8A = 80
-8P + 10A = 20
And add them to get 2A = 100, which means A = 50
If A = 50, then we know that P = 60 (just plug A = 50 into one of the equations and solve for P)
Cheers,
Brent
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We are given that all apples are equally priced and all pears are equally priced, and we need to determine the price of a pear. We can let p = the cost of a pear in cents and a = the cost of an apple in cents.mArikIo wrote:I am having some problems with the follwing question and would really appreciate some help.
If all apples at a certain grocery store are equally priced, all all pears at the grocery store are equally priced, what is the price of a pear?
(1) Eight pears cost eighty cents more than eight apples
(2) Ten apples cost twenty cents more than eight pears
Statement One Alone:
Eight pears cost eighty cents more than eight apples.
Using the information in statement one, we can create the following equation:
8p = 8a + 80
p = a + 10
While we know a pear costs 10 cents more than an apple, we cannot determine the value of p. Statement one alone is not sufficient to answer the question. We can eliminate answer choices A and D.
Statement Two Alone:
Ten apples cost twenty cents more than eight pears.
Using the information in statement two, we can create the following equation:
10a = 8p + 20
5a = 4p + 10
While we know 5 apples cost 10 cents more than 4 pears, we cannot determine the value of p. Statement two alone is not sufficient to answer the question. We can eliminate answer choice B.
Statements One and Two Together:
Using statements one and two, we know that p = a + 10, or p - 10 = a, and that 5a = 4p + 10. If we substitute (p - 10) for a in the equation 5a = 4p + 10, we have:
5(p- 10) = 4p + 10
5p - 50 = 4p + 10
p = 60
Answer: C
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