Functions & Percentage problem

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Functions & Percentage problem

by golu23 » Sun Jan 29, 2012 7:46 pm
1) For every positive integer n, the function (n)his defined to be the product of all integers 2 to n inclusive, If p is the smallest prime factor of h(100)+1 then p is
a)Between 2-10
b)10-20
c)20-30
d)30-40
e)Greater than 40

In this question i figured out that the answer is "E" but wasn't able to solve it mathematically could someone please tell me how to do it.


2) Connie paid a sales tax of 8% on her purchase If the sales tax had been only 5% she would have paid 12$ less in taxes on her purchase. What was the total amount for her purchase including tax?
a)368
b)380
c)400
d)420
e)432.

For this problem tried many smart nos but i just couldn't figure it out.
Source: — Problem Solving |

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by Jim@StratusPrep » Mon Jan 30, 2012 9:59 am
1) H(100) is divisible by every prime factor less than 100, thus when you divide those same prime factors into H(100) + 1 you will always get a remainder of 1. So, actually the smallest prime factor must be greater than 100.


2) You are just looking at the difference here. 3% of what number equals 12. 400 is the answer, or "C"
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by golu23 » Wed Feb 01, 2012 6:57 am
Thanks Jim could u also let me know how to solve these.

The residents of town X participated in a survey to determine the no of hours per week each resident spent
Watching TV. The distribution of the results of the survey had a mean of 21 hrs and a std deviation of6 hrs. The no of hrs PAT watched TV last week was between 1 &2 std deviations below the mean. Which of the foll could be the no that pat watched TV?

a)30 b)20 c)18 d)12 e)6.

3)In the XY coordinate plane system the slope of the line is -3/4.Does the line L pass through the point(-2/3, 1/2)?
A)Line L passes through the point (4, 4)
B)Line L passes through the point (-4,-2)

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by Jim@StratusPrep » Wed Feb 01, 2012 9:00 am
See here for the definition of standard deviation

So you are looking for something that is between 6 and 12 hrs below 21 or between 9 and 15 --> D)12



Next problem:

See here for definition of slope

If you have the slope of a line and a single point you can figure out all other points that are on the line.

Therefore, D is the answer.
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