Final answer:
The total round trip time for Xavier to pick up Olivia and return is approximately 20.76 minutes, assuming the speed to Olivia's house is 30 mph and it is 2 mph slower on the way back.
Step-by-step explanation:
To calculate the expression for the total travel time for the round trip, we need to account for the speed difference when Xavier travels alone versus when he's with Olivia. If the average speed when Xavier rides alone to Olivia's house is 30 mph, and it's 2 mph less on the way back, we have:
Speed to Olivia's house: 30 mph
Speed back to Xavier's house: 30 mph - 2 mph = 28 mph
The distance to and from Olivia's house is 5 miles each way. To find the time for each leg of the trip, we use the formula time = distance / speed.
Time to Olivia's house: time = 5 miles / 30 mph = 1/6 hours
Time back to Xavier's house: time = 5 miles / 28 mph ≈ 0.179 hours
Add the times together for the total travel time:
Total travel time ≈ 1/6 hours + 0.179 hours ≈ 0.346 hours.
To convert this to minutes, multiply by 60:
Total travel time in minutes ≈ 0.346 hours x 60 ≈ 20.76 minutes.
Therefore, the entire round trip takes approximately 20.76 minutes.