The speed of the Elvira is 6.545 miles per hour. Then the speed of the Altheia will be 0.545 miles per hour.
<h3>What is speed?</h3>
The distance covered by the particle or the body in an hour is called speed. It is a scalar quantity. It is the ratio of distance to time.
We know that the speed formula
Speed = Distance/Time
Let the speed of the Elvira be x. Then the speed of the Altheia will be (x - 6).
Let the distance between the coffee shop and Elvira's house be d.
Then the distance between the coffee shop and Altheia's house will be (3.6 - d).
Then we have
x = d / 0.5 ...1
(x - 6) = (3.6 - d) / 0.6 ...2
In solving the equations 1 and 2, we have
x = 6.545 and d = 3.2725 miles
Then the speed of the Elvira is 6.545 miles per hour. Then the speed of the Altheia will be 0.545 miles per hour.
More about the speed link is given below.
brainly.com/question/7359669
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