Common Core State Standards | Math | CK-12 Foundation CK-12 CONCEPTS Unit Rates Rates of Change 6.RP.A.3.C Find a percent of a quantity as a rate per 100 (e.g., 30% of a quantity means 30/100 times the quantity); solve problems involving finding the whole, given a part and the percent. CK-12 CONCEPTS Percent Problems Unit Rates The Percent Equation 6.RP.A.3.D