Some help with questions from gmatprep

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Some help with questions from gmatprep

by gman » Fri Nov 14, 2008 12:59 am
I have a few questions from my first gmatprep1 test that I need some explanations on if anyone is familiar with them. I have my test coming up in a week and I am stessed as my quant score wasn't up to my expections so I appreciate any details explanations that can help my studies. thanks


1)The perimeter os a certain isosceles right triangle is 16 + 16 <2>. What is the length of the hypoteneuse?

<>= radical

2) if the speed of x meters per second is equivalent to the spped o y km per hr what is y in terms of x ?

3) A quality control check is made by inspecting a sample of 2 lightbults from a box of 12 lightbultbs. how many different samples can be chosen?

4) For which of the following function f if f(x)-f(1-x) for all x?

5) N is a positive integer. Is the units digit of N equal to zero?
N=2^5 3^2 5^7 7^6

6) In a certain deck of cards, each card has a positive integer written on it. In a multiplication game a child draws on the card by the next larger integer. If each possible product is between 15 and 200 then the least and great integers on the card could be
a) 3 and 15
b) 3 and 20
c) and 13
etc

7) Three grades of milk are 1 percent, 2 percent, and 3 percent fat by volume. If X gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to givce x + Z + Y gallons of a 1.5 percent grade, what is x in terms of y and z?
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Re: Some help with questions from gmatprep

by iamcste » Fri Nov 14, 2008 3:51 am
gman wrote:I have a few questions from my first gmatprep1 test that I need some explanations on if anyone is familiar with them. I have my test coming up in a week and I am stessed as my quant score wasn't up to my expections so I appreciate any details explanations that can help my studies. thanks


1)The perimeter os a certain isosceles right triangle is 16 + 16 <2>. What is the length of the hypoteneuse?

<>= radical

2) if the speed of x meters per second is equivalent to the spped o y km per hr what is y in terms of x ?

3) A quality control check is made by inspecting a sample of 2 lightbults from a box of 12 lightbultbs. how many different samples can be chosen?

4) For which of the following function f if f(x)-f(1-x) for all x?

5) N is a positive integer. Is the units digit of N equal to zero?
N=2^5 3^2 5^7 7^6

6) In a certain deck of cards, each card has a positive integer written on it. In a multiplication game a child draws on the card by the next larger integer. If each possible product is between 15 and 200 then the least and great integers on the card could be
a) 3 and 15
b) 3 and 20
c) and 13
etc

7) Three grades of milk are 1 percent, 2 percent, and 3 percent fat by volume. If X gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to givce x + Z + Y gallons of a 1.5 percent grade, what is x in terms of y and z?

Pls post the entire question with options.

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by stop@800 » Fri Nov 14, 2008 7:48 am

The perimeter os a certain isosceles right triangle is 16 + 16 <2>. What is the length of the hypoteneuse?



Perimeter is 16 + 16sqrt(2)

sides will be s s sqrt(2)*s
sum will be

2s + sqrt(2)*s = 16 + 16sqrt(2)
solve you will get s as
16/sqrt(2)

alternately u can adjust

16 + 16sqrt(2)
as
2s + sqrt(2)*s
and find s

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by stop@800 » Fri Nov 14, 2008 7:48 am

if the speed of x meters per second is equivalent to the spped o y km per hr what is y in terms of x ?

y km/hr

y * 1000 / 3600 m/s

5y/18 = x
so
y = 18x/5

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by stop@800 » Fri Nov 14, 2008 7:48 am

A quality control check is made by inspecting a sample of 2 lightbults from a box of 12 lightbultbs. how many different samples can be chosen?

12c2 = 11*6 = 66

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by stop@800 » Fri Nov 14, 2008 7:54 am

For which of the following function f if f(x)-f(1-x) for all x?

The options are actually needed and also
I think the question is
f(x) = f(1-x)
Solved lot many times in this forum, just search.




N is a positive integer. Is the units digit of N equal to zero?
N=2^5 3^2 5^7 7^6


units digits: 2 * 9 * 5 9
= 0 [keep only unit digit]






In a certain deck of cards, each card has a positive integer written on it. In a multiplication game a child draws on the card by the next larger integer. If each possible product is between 15 and 200 then the least and great integers on the card could be
a) 3 and 15
b) 3 and 20
c) and 13
etc


I think question is incomplete
let me still try
15
4 * 5
so minimum is 4

200
13 * 14 = 182
so maximum is 13


answer 4..13



7) Three grades of milk are 1 percent, 2 percent, and 3 percent fat by volume. If X gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to givce x + Z + Y gallons of a 1.5 percent grade, what is x in terms of y and z?

Solved lot many times in this forum, just search.

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by mental » Sat Nov 15, 2008 5:03 am
In a certain deck of cards, each card has a positive integer written on it. In a multiplication game a child draws on the card by the next larger integer. If each possible product is between 15 and 200 then the least and great integers on the card could be
a) 3 and 15
b) 3 and 20
c) and 13
etc


I think question is incomplete
let me still try
15
4 * 5
so minimum is 4

200
13 * 14 = 182
so maximum is 13


answer 4..13
shouldnt it be 3 and 20?

least possible product is 15
3 * 5 = 15

200 = 20 * 10

using the given answer choices: 200 is not a multiple of 13 or 15

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Re: Some help with questions from gmatprep

by rackbar » Fri Nov 28, 2008 9:19 pm
gman wrote: 5) N is a positive integer. Is the units digit of N equal to zero?
N=2^5 3^2 5^7 7^6



7) Three grades of milk are 1 percent, 2 percent, and 3 percent fat by volume. If X gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to givce x + Z + Y gallons of a 1.5 percent grade, what is x in terms of y and z?
Assuming that you're multiplying in 5, as A shortcut, you know that since 5 is a factor, N must end in either 5 or zero. Furthermore, since two is a factor, N must be even and therefore, the units digit must be zero.


Also, for 7 i got that x = 4y + 3z, I'll explain my work if you can confirm that that's the correct answer.
________

GmatPrep 1: 770, Q50 V44
Kaplan CAT 1: 660, Q44, V41
Kaplan CAT 2: 670, Q50, V37
Kapaln CAT 3: 500, Q50, V8
GmatPrep 2: 770, Q50, V45

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by pramandra2001 » Sat Nov 29, 2008 12:25 am
I beleive the answer to the first question (The perimeter os a certain isosceles right triangle is 16 + 16 <2>. What is the length of the hypoteneuse? ) is 16 (SIXTEEN)...this is how I approached..
Assuming s to the sides and h to be the hypotenuse, we are given that,
s+s+h = 16 + 16 <2>
2s + h = 16 (1+<2>) ----(1)

From the rt angle triangle,
s^2 + s^2 = h^2
so <2> s = h
s = (1/<2>) h -------(2)
using (2) in (1),
2* (1/<2>)* h + h = 16 (1+<2>)
<2> h +h = 16 (1+<2>)
(1+<2>) h = 16 (1+<2>)
so h = 16
Pls correct me if I am wrong....

THanks
VJ