Helga and Dora were solving the following problem together. A boat left Kyuquot and headed west at 15.5 km/h. A second boat left Kyuquot half an hour later and headed west at 18 km/h. For how many hours did the first boat travel before the second boat overtook it? Both girls used t to represent the time taken by the first boat. However, they disagreed on the equation to model the situation. Helga’s Equation Dora’s Equation 15.5t = 18(t + 0.5) 15.5t = 18(t - 0.5) a) Explain what the expression on each side of each equation represents. b) Which equation is correct? Explain. c) What is the solution to the problem?