TCURF, TCURR and TCURX

TCURF is always used in reference to Exchange rate.( in case of currency translation ).For example, Say we want to convert fig's from FROM curr to TO curr at Daily avg rate (M) and we have an exchange rate as 2,642.34. Factors for this currency combination for M in TCURF are say 100,000:1.Now the effective exchange rate becomes 0.02642.
Question ( taken from sdn ):
can't we have an exchange rate of 0.02642 and not at all use the factors from TCURF table?.I suppose we have to still maintain factors as 1:1 in TCURF table if we are using exchange rate as 0.02642. am I right?. But why is this so?. Can't I get rid off TCURF.
What is the use of TCURF co-existing with TCURR.
Answer :
Normally it's used to allow you a greater precision in calaculations
ie 0.00011 with no factors gives a different result to
0.00111 with factor of 10:1

So basing on the above answer, TCURF allows greater precision in calculations.
Its factor shud be considered before considering exchange rate.
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TCURR
TCURR table is generally used while we create currency conversion types.
The currency conversion types will refer to the entries in TCURR defined against each currency ( with time reference) and get the exchange rate factor from source currency to target currency.
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TCURX
TCURX table is used to exactly define the correct number of decimal places for any currency. It shows effect in the BEx report output.
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