Mass & Diameter

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Mass & Diameter

by golu23 » Sat Feb 04, 2012 9:07 am
The mass of 1 cubic centimeter of a substance is 800kg under certain conditions. What is the volume of 1 gram of this substance under these conditions? (1kg=1000grams and 1 cubic meter=1000000 cm)
a)0.80,
b)1.25,
c)8.00,
d)12.5,
e)80

The diameter of a circle S is equal in length to side of a square. The diameter of a circle T is equal in length to a diagonal of the same square. The area of circle T is how many times the area of circle S ?
a)Sq rt 2,
b)Sq rt 2+1
c)2
d)Pie,
e)Sq rt 2pie

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by bryan88 » Sat Feb 04, 2012 11:27 am
1) Answers should have unit.

2) Diameter of circle S =x
Diameter of circle T =Sqrt x

Ratio of area of T/Ratio of area of S= 2 :1

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by WhiteWNNoise » Sat Feb 04, 2012 12:04 pm
1. The information seems to be wrong. I think the question should start with "The mass of 1 cubic meter of a substance......" . The answer would then be 1.25 cubic centimeters.

2. r(s) = radius of circle S
r(t) = radius of circle T

Circle S: 2r(s) = s/2 ....... r(s) = s/2
Circle T: 2r(t) = (sqrt 2)s ....... r(t) = s/(sqrt 2)

Area T / Area S = 2 : 1

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by Anurag@Gurome » Sun Feb 05, 2012 6:01 pm
golu23 wrote:The mass of 1 cubic centimeter of a substance is 800kg under certain conditions. What is the volume of 1 gram of this substance under these conditions? (1kg=1000grams and 1 cubic meter=1000000 cm)
a)0.80,
b)1.25,
c)8.00,
d)12.5,
e)80
For this one, I have posted a solution here: https://www.beatthegmat.com/mass-and-vol ... 93635.html
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by Anurag@Gurome » Sun Feb 05, 2012 6:09 pm
golu23 wrote: The diameter of a circle S is equal in length to side of a square. The diameter of a circle T is equal in length to a diagonal of the same square. The area of circle T is how many times the area of circle S ?
a)Sq rt 2,
b)Sq rt 2+1
c)2
d)Pie,
e)Sq rt 2pie
Let the diameter of a circle S = X, diameter of a circle T = Y and the length of side of a square = S
Now, diameter of a circle T is equal in length to a diagonal of the same square implies Y = √(2S²) = S√2
Area of circle T = (pi)(Y/2)² = Y²(pi)/4 = 2S²(pi)/4
Area of circle S = (pi)(X/2)² = X²(pi)/4 = S²(pi)/4
So, area of circle T = 2 * area of circle S

The correct answer is C.
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