PR CAT QUESTIONS

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PR CAT QUESTIONS

by nasharussia » Fri May 29, 2009 8:44 am
I got two problems that Im struggeling to comprehand how the PR came up with the solutions.

Darla typed her term paper for two hours without a break. If her average words-per-minute speed increased by 20% in the second hour and her term paper was 7,920 words long, what was her typing speed during the second hour?

Choices A 50 B 60 C 62 D 72 E 79

I looked an answer up after completing their cat, and i still cant figure out how they arived with an answer! The numbers dont match! I thought it was my algebratic misstake so I solved it again with the calculator, and despite my minor misstake in addition, the number still didnt match. Can anyone tell me, is that me going stupid after studying intensly or the PR has issues on their cat's?

Also second Problem I struggle with on the same cat:

m and n are the x and y coordinates, respectively, of a point in the coordinate

plane. If the points (m, n) and both lie on the line defined

by the equation , what is the value of p?
A. 4/5 B. 1 C. 2 D. 5 E. 8

This one i am kind of getting their explanation but in it they come with a number that seem to appear out of the thin air and then just as magically dissapears. So im really confused about this problem as well. Their official answers are D for the first question and C for the second one. Ill post few more questions later cause PR's explanations just kill me at times...
Source: — Problem Solving |

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by ssmiles08 » Fri May 29, 2009 9:00 am
1. For the first 60 min you have rate r, and for the second 60 minutes you have rate 1.2r (rate increases by 20%)

The total amount Darla typed was 7920.

So what you would do is add the two amounts for the first two hours to add up to 7920.

For the amount of words she typed for the first hour would be (r)(60)

For the amount of words she typed for the second hour would be (1.2r)(60)

amount1 + amount2 = 7920

60r + 72r = 7920; 132r = 7920

r = 60.

Now the question asks for the rate for the second hour: 1.2(60) = 72 words per minute