Has anyone come upon rounding errors when doing math calculation and in particular to a cost being multiplied by a markup

I do not see this every time but it does happen on certain costs. In the example below you will see what is happening

• 4 x 39.87 and the result is 159.46....should be 159.48
• 2 x 117.03 and the result is 234.05....should be 234.06

Ones that are right

• 2 x 56.19 and the result is 112.38
• 2 x 52.67 and the result is 105.34

I have looked at all of my cost items and they only are entered out to two decimal points, but when I look and the sale after the cost is multiplied by the markup, the result for the individual sale price goes out several decimal points yet I only have it set to two. There is definitely some rounding up and down going on and not sure how to fix that since it is only happening sporadically.