Emily and holly took a road trip together. emily drove at an average of 45 miles per hour for the first 3/7 of the total distance, and holly drove the last 24 miles at an average rate of 54 miles per hour. how long did the trip take the two of them? give your answer in terms of hours.

Emily drove 3/7 of the total distance and holly drove the rest which explains that holly drove 4/7 of the whole distance.

if 4 parts of the distance equals 24 miles, then 1 part would be 24/4 is 6.
since emily drove 3 parts of the whole distance, it is 6 × 3 = 18 miles.

travelling time of emily = 18/45 = 0.4 hr
travelling time of holly = 24/54 = 0.4 hr
--> total traveling time = 0.8 hr

i hope it is right