Think about how much money you're budgeting for the trip. Or, if you know how much money you'll need in the other country, work backwards and start with the foreign currency. You can find this information on a Google search, or on several banking or financial websites. Note that you want to set the currency you have to 1; the value listed next to the currency you're exchanging to is the exchange rate. Multiply the money you've budgeted by the exchange rate.  The answer is how much money you'll have after the exchange.  If "a" is the money you have in one currency and "b" is the exchange rate, then "c" is how much money you'll have after the exchange.  So a * b = c, and a = c/b.  For instance, say you want to convert Euros to US dollars.  At the time of this revision, 1 Euro is worth 1.09 US dollar.  Your exchange rate is 1.09.  If you're planning on taking $1500 Euros with you, you would multiply 1500 by 1.09.  The answer, 1632.61, is how much money you'll have in dollars after the exchange. Here's an example of the "work backwards" method.  Say that you know you'll need 20,000 Hungarian forints for your trip. You discover that 1 US dollar is equivalent to 226.43 forints. To figure out how many US dollars you would need to save at the current exchange rate, divide 20,000 by 226.43.  The answer, 88.33, is how many US dollars you need to exchange.

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Write a summary of the previous text in Indonesian:
Perkirakan jumlah uang yang ingin ditukarkan. Cari kurs mata uang yang ingin ditukarkan. Hitunglah banyaknya uang yang akan dimiliki pascapenukaran.