ANSWER
72km/h
EXPLANATION
The average speed of the car can be calculated using the formula:
Average Speed=total distance/ total time taken.
The car covers a distance of 108km in 1½ hours.
We substitute the values into the formula to obtain,
Therefore the average speed of the journey is 72km/h
Answer:
0.2071
Step-by-step explanation:
It looks like the graph is of the function ...
y = √(x +8) -2
We know that (-4, 0) is one point on the graph. The other point of interest is at x=0, where y = √8 -2 ≈ 0.8284.
The average rate of change on the interval is then ...
m = (0.8284 -0)/(0 -(-4)) = 0.2071
The average rate of change on the interval is about 0.2071.
_____
<em>Rougher estimate</em>
The graph goes through the points (-4, 0) and (1, 1), so has a slope of 1/5 = 0.2 on the interval [-4, 1]. We know the graph does not go through (0, 1), so the slope is not as high as 1/4 = 0.25. The curve is concave downward, so the average slope will be higher than 0.2, but we aren't sure how much higher.
A reasonable estimate of the rate of change on the interval is "a little more than 0.2, but less than 0.25."
