Quadri-, quadru-, quadr-is a Latin prefix related to the verb quadrare âto make squareâ, quadratus âsquareâ etc. Quad is simply an English shortening of quadrangle, quadruplet etc. So quadri-and quad are actually the same word.
The Washington state sales tax rate is 6.5% , and the average WA sales tax after local surtaxes is 8.89% 1  . Groceries and prescription drugs are exempt from the Washington sales tax. 2  Counties and cities can charge an additional local sales tax of up to 3.1%, for a maximum possible combined sales tax of 9.6%.
6.5% is the smallest possible tax rate (98060, Seattle, Washington) 10% are all the other possible sales tax rates of Seattle area. 10.1% is the highest possible tax rate (98101, Seattle, Washington) The average combined rate of every zip code in Seattle, Washington is 9.699%. Other 2018 sales tax fact for Seattle