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value of antique watch..

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value of antique watch..

by ska7945 » Fri Aug 22, 2008 10:57 pm
At the end of each year, the value of a certain antique watch is c percent more than its value one year earlier, where c has the same value each year. If the value of the watch was k dollars on January1, 1992, and m dollars on January 1, 1994, then in terms of m and k, what was the value of the watch, in dollars, on January 1, 1995
1.m+(1/2)(m-k)
2.m+(1/2)((m-k)/k)m
3.m sqrt m/sqrt k
4.m^2/2k
5.k(m/^2)


oa c
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Re: value of antique watch..

by sudhir3127 » Fri Aug 22, 2008 11:34 pm
ska7945 wrote:At the end of each year, the value of a certain antique watch is c percent more than its value one year earlier, where c has the same value each year. If the value of the watch was k dollars on January1, 1992, and m dollars on January 1, 1994, then in terms of m and k, what was the value of the watch, in dollars, on January 1, 1995
1.m+(1/2)(m-k)
2.m+(1/2)((m-k)/k)m
3.m sqrt m/sqrt k
4.m^2/2k
5.k(m/^2)


oa c
Its C

Assume the value in 92 as K
in 93 it will be K + c*K ( increases C %)
= K(1+C)

in 94 its
K(1+c)^2

given m=k*(1+c)^2................................................1

in 95 the value will be k*(1+c)^3
this can be written as
k*(1+c)^2* (1+c)
using 1 we can re write it as

m(1+c) ........( since m=k*(1+c)^2 from 1)...................................2

we know from 1 that
(1+c)^2 = m/k

thus 1+c = sqrt m/sqrt k................................................3

by using 3 in 2 we can rewrite 2 as

m* sqrt m/sqrt k

which is
m*(sqrt(m/k) )

hope it helps..
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by crackgmat007 » Thu Aug 06, 2009 3:25 pm
I tried solving the above question using plug ins but with limited luck. Did any one try using plug ins? Pls solve.
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by aspiregmat » Thu Aug 06, 2009 9:51 pm
Tried using plugin

let k = 100
c = 10
then m = 121

actual ans = 133.1

we see that 133.1 is a cube... so answer should have cube of 11

In terms of m it means msqrt(m)

so Ans = C
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