According to the rule of 70, how many years will it take an investment that is making 4.5 percent interest to double in size? a) 70 years b) 15.56 years c) 31.5 d) 4.5years

Barney & noblet customers can choose to purchase a membership for $25 per year members receive 10% off all store purchases 1. how much would a member pay per year if he bought $50 worth of items each year? 2. write a slope-intercept equation that expresses how much a member pays per year using x to represent his purchases per year 3. how much would a member have to spend per year to pay off his membership fee?