Heuristics to highlight

Act it out; Draw a diagram; Restate the problem in another way; Aim for sub-goals

On a Tuesday, Alice, Bernice and Carol and Dory, met for a movie. After the movie, they made plans for the next gathering. Alice, Bernice and Carol said that they could only go to the movies every 6, 3 and 4 days respectively, starting from that Tuesday. Dory said that she could go to the movies every day except on Fridays. After how many days would the four friends be able to meet again for a movie?