More Primes

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by tirupathirao » Sat Oct 22, 2011 10:00 am
We have four colors
so we have to frame the euatation like this
1*5*x*11=88000
=88*1000
=11*8*(25*4*10)
11*5^3*8^2*11

if we compare both LHS and RHS we have x=2

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by rooster » Tue Oct 25, 2011 5:35 pm
duongthang wrote:I can not understand why X can not be 10, Pleas, explain more on this
It says that x is between 5 and 11, we also need to know what numbers can be broken down into primes.

88,000 = (11)(10^3)(8) OR (11)(2*2*2*5*5*5)(2*2*2)

Since we know 5 is one of the chips, we can take 5 out of the equation, and then we are left with a number of 2s.

We also know x>5, so x must be 8 since we know there is only one additional chip and it cannot be greater than 11. IF the other chip was 10, we would be left with a number of 2's that are not part of the equation since there are 4 chips, none listed as 2.

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by immaculatesahai » Sat Nov 05, 2011 12:05 am
Ans: B (2chips)

Bag contains- Blue (1) Green (5) Purple (x) Red (11)

We know x>5, x<11.

Factorize 88000, you will get factors of 11,5,5,5,8,8. Hence the value of x is 8 and there are 2 purple chips.

There is the possibility of the value being 10, but dividing by 10 will also leave eventual remainder to 2 (which we dont want).

Simple problem.

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by nskandan » Thu Nov 24, 2011 11:45 am
Thang Do wrote:I think the short way should be:

As in the context:

(1^a).(5^b).(x^c).(11^d)=88000

a,b,c,d is the numbers of each colour chip.

So we have to find what is c.

To find c we need find x. We will break 88000 in to 1, 5, 11 as follows:

88000 = 88.1000 = 11.8.1000 = 11. 8. 5.5.5.8 = 11.8.8.5.5.5

So

(1^a).(5^b).(x^c).(11^d)=88000 = 5.5.5.8.8.11

Because 1.1.1...1 = 1 so we dont care what is "a".

as we know that 5<x<10 so x= 8 is reasonable.

Thus

5^b = 5.5.5 --->b = 3
x^c= 8^c = 8.8=8^2 ---> c = 2 -----> answer is B
11^d= 11---> d = 1

By this way we can find a,b,c,d
Please clarify this beginners doubt.

If b is number of pieces and 5 is the price per piece then net Value of chip should be 5*a . Why we are taking 5^a ?
NSK

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by Ramesh L.S. » Mon Nov 28, 2011 2:40 am
Imagine I select 17596[ worth 87980 points]green chips,I am left with 20 points, in that i accomodate 1 Red chip, Now I am left with 9 points to accomodate, i will select 1 purple chip [worth 9 points, i.e. greater than 5 but less than 11], according to me answer is option A. please let me know if something is missing.

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by Ramesh L.S. » Mon Nov 28, 2011 2:47 am
i got it, i was actually adding the points instead of multiplying,

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by thunderdan » Wed Dec 21, 2011 7:03 am
This is one of those questions, I will definitely guess and move on in the test. If you try to solve it thoroughly it will take a lot of time; which many of us do not have during the test.

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by ronnie1985 » Wed Dec 28, 2011 6:56 am
88000 = 8x11x1000
8=2^3
and 1000 = 10^3
The value of Purple chips can either be 2 or 4. If it is 2 then no of purple chips should be 6, but no such option is available. therefore the value of purple chip is 4 and the no of purple chips is 3.
Answer = (C)
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by gmattest001 » Sat Feb 04, 2012 9:44 am
Answer will be 2 .
B

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by rajeev_ranjan » Sat Feb 11, 2012 3:20 am
i think the question should ask maximum no. of purple chips... as in the current scenario purple chips can be one and 8 blue chips.
pl correct me if i am wrong..

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by ka_t_rin » Tue Mar 13, 2012 7:34 am
The answer is B - 2 purple chips.
We shound use prime factorization to see how it works out:

88000 = 1000 * 11 * 8 = 2^3 * 5^3 * 11 * 2^3
Thus we see that there are 3 green chips and one red.
The purple one costs between 5 and eleven, so we can deduce that there are 2 purple chips at 8 points each!!!)))))))) Pretty easy )

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by ka_t_rin » Tue Mar 13, 2012 7:35 am
See my answer below ;)))
rajeev_ranjan wrote:i think the question should ask maximum no. of purple chips... as in the current scenario purple chips can be one and 8 blue chips.
pl correct me if i am wrong..

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by ka_t_rin » Tue Mar 13, 2012 7:38 am
DONT FORGET that x is between 5 and 11. It can`t be 20)
And that 10^3 = (5*2)^3
ronnie1985 wrote:88000 = 8x11x1000
8=2^3
and 1000 = 10^3
The value of Purple chips can either be 2 or 4. If it is 2 then no of purple chips should be 6, but no such option is available. therefore the value of purple chip is 4 and the no of purple chips is 3.
Answer = (C)

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by KAS1 » Fri Mar 16, 2012 6:26 am
Would you consider this a 600 or a 700 level question?

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by prashantsarode » Mon Apr 09, 2012 2:01 am
88,000 = 11*5*5*5*2*2*2*2*2*2

means 88,000 = 11*5^3*2^3

As value of purple should be between 7 and 11 2^3 can be organised as 8*8.

Hence answer should be B i.e. 2