Answer:
5 miles per hour
Step-by-step explanation:
Let the speed of Kelly is miles per hour and speed of Raul is v₂ miles per hour.
Since, speed =
Kelly took 135 minutes to cover 90 miles from New York to Philadelphia.
∵ 1 minute = hours
∴ 135 minutes = =
hours
v₁ =
=
= 40 miles per hour
Raul took 153 minutes to cover the same distance as Kelly,
∵ 1 minute = hours
∴ 153 minutes = =
hours
v₂ =
= 35.29
≈ 35.3 miles per hours
v₁ - v₂ = 40 - 35.3
= 4.7
≈ 5.0 miles per hours
Therefore, Kelly is 5 miles per hours faster than Raul.