Answer:
120 miles/hour
Explanation:
The average speed is the ratio of total distance covered by an object or a body to the total time taken to cover the distance.
Mathematically,
<em>Average speed = total distance covered/total time taken</em>
In the case of Connie:
total distance = 180 + 180 = 360 miles
In order to calculate the time for each trip
<em>speed = distance/time</em>
<em> time = distance/speed</em>
From Phoenix to flagstaff:
time = 180/180 = 1 hour
From flagstaff back to Phoenix:
time = 180/90 = 2 hours
total time taken = 1 + 2 = 3 hours
Average speed = 360/3 = 120 miles/hour
<em>Hence, the average speed is </em><em>120 miles per hour.</em>
