Re: sorry .09 instead of .08

joshdalrymple2000@xxxxxxxxx wrote: 
double totalCost = 3.91, amountPaid = 4.00;
int totalChange;


totalChange = (int)((amountPaid - totalCost) * 100);
System.out.println(totalChange);


it keeps saying the answer is 8... can any one help?

Never ever perform money calculation using floating point.
First solution : use BigDecimal and BigInteger (which are slower, as mentioned before).
Second solution (used in all our banking applications) : specify the amounts in "smallest currency unit" (cents for $, pence for pounds), and associate a "small unit number" with each currency (if you need to manage several currencies), which specifies the number of small units needed for GUI.
For instance, for $, calculations are made in cents, and display is done with amount/100 $ and amount%100 cents (small unit number = 2)
.

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