The sales tax for an item was $19.50 and it cost $390 before tax. Find the sales tax rate. Write your answer as a percentage.

Iq scores for adults age 20 to 34 years are normally distributed according to n(120, 20). in what range does the middle 68% of people in this group score on the test?

Suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet.

How do the number line graphs of the solutions sets of -23 > x and x-23 differ?