Final answer:
To determine who is the fastest, we need to compare the rates of running between Elvis and Lucy. Lucy is the fastest runner as she has a higher rate than Elvis.
Step-by-step explanation:
To determine who is the fastest between Elvis and Lucy, we need to compare their rates of running. Rate is determined by dividing the distance traveled by the time taken.
Elvis runs 5/6 of a mile in 1/6 of an hour, therefore his rate is 5/6 ÷ 1/6 = 5 miles per hour.
Lucy runs 7/8 of a mile in 1/8 of an hour, therefore her rate is 7/8 ÷ 1/8 = 7 miles per hour.
Therefore, Lucy is the fastest runner, as she has a higher rate than Elvis.