Jan bought a blazer for 39.90. The price of the blazer was 38. What sales-tax rate was she charged for this blazer?

To find the sales tax rate, we first calculate the amount of sales tax paid. Jan paid $39.90 for the blazer, which cost $38. The sales tax is $39.90 - $38.00 = $1.90. To find the sales tax rate, we divide the sales tax by the original price: $1.90 / $38.00 = 0.05, or 5%. Therefore, the sales tax rate charged was 5%.