If i gave you the ratio of 15: 24 and told you that it had to do with the number of students in a class, what are 2 different possibilities for what 15 and 24 could represent?

Johnny rode his bike to a friends house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was unable to play. what was his displacement for the total bike ride trip? what could you use as a reference point ? show the steps to solve this problem.