On a rainy day, every kid at Margo's school brings a raincoat, an umbrella, or both. And 18% of the kids bring both. The total number of umbrellas brought is twice the total number of raincoats. What percent of the kids bring only an umbrella?
x = raincoats 2x = umbrellas
x-18 = coats only 2x-18 = umb only 18% = both sums to 100%
x - 18 + 2x-18 + 18 = 100 %
3x = 118
x = 39. 33 % then 2x-18 = 60.67 % bring umbrella only