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?


Try looking at the output of this instead

	double totalCost = 3.91, amountPaid = 4.00;
        double totalChange;


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

You'll see it isn't 9, and the cast to int truncates it to 8, as you were seeing originally.

The problem is that you can't use floating point arithmetic (doubles) to do precise arithmetic. If possible then you should try using fixed point arithmetic. e.g.

	int totalCost = 391, amountPaid = 400;
	int totalChange;

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


James
.

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