Fiona and Diana are sisters. They each baked cookies. Fiona baked 15 more cookies than Diana. They baked a total of 75 cookies. How many cookies did each girl bake?

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.