He will need 24 more hours. Hopefully helpful
Answer:
give me 1 second to answer with the correct answer
A) Divide total miles by total time:
21 miles / 4 hours = 5.25 miles per hour.
B) Divide miles by miles per hour:
42 miles / 5.25 miles per hour = 8 hours.
For the first one, to find the missing fraction, add the first two fractions and subtract that from the last fraction. For the second question, subtract the first two fractions then add that to the last fraction. Hope this helps.