bullion downgrading

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bullion downgrading

by sanju09 » Sat Feb 21, 2009 6:18 am
Gold depreciated at a rate of x% per year between 2000 and 2005. If 1 kg of gold cost S dollars in 2001 and T dollars in 2003, how much did it cost in 2002?
A. T (S/2)
B. T sqrt (T/S)
C. T sqrt (S)
D. T [S/sqrt (T)]
E. sqrt (S T)
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by sureshbala » Sat Feb 21, 2009 6:36 am
The answer must be E.

Instead of going theoretically, it would be quick if you can go for numbers. Let's say the price depreciates by 10% and let the price in 2001 be 100.

2001:100 (given as S)

2002: 90

2003: 81 (given as T)

We can observe that 90 = sqrt(100x81) = sqrt(ST)