In a triathlon, jenny swam for 1 hour, biked for 1.75 hours, and ran for 1 hour. her average biking speed was 2 times her average running speed, and her average running speed was 8 times her average swimming speed. the total distance of the triathlon was 55.5 kilometers. write and solve a linear equation to calculate jenny’s average swimming speed (x) in kilometers per hour. give your answer to the nearest tenth.