WGW Manufacturing produce basic work shirts. The manufacturer quotes a list price of $29.90 for the shirts. WGW offers a regular trade discount of 25% to wholesalers. They also offer a volume discount of 10% on any order of at least 1,000 shirts. What single discount rate will give the same price per shirt as the two discounts combined? (Final answer as a percent to 1 decimal place, do NOT include percent sign)