Let's do some math ..  Rounding examples of 7 random hypothetical purchases:
Case	Tag   Price	Sales   Tax %	Raw Total   Incl. Sales Tax	Rounded   to Penny	Rounded   to Nickel	Rounded   to Dime
Purchase #1	$88.74	7.817%	$95.6768	$95.68	$95.70	$95.70
Purchase #2	$144.52	6.492%	$153.9022	$153.90	$153.90	$153.90
Purchase #3	$142.85	5.734%	$151.041	$151.04	$151.05	$151.00
Purchase #4	$191.45	3.190%	$197.5573	$197.56	$197.55	$197.60
Purchase #5	$57.88	13.179%	$65.508	$65.51	$65.50	$65.50
Purchase #6	$189.29	5.387%	$199.4871	$199.49	$199.50	$199.50
Purchase #7	$172.71	10.287%	$190.4767	$190.48	$190.50	$190.50
7 purchase totals =	$987.44		$1,053.6491	$1,053.66	$1,053.70	$1,053.70