Question

The graph shows the distance, y, in miles, of a moving motorboat from an island for a certain amount of time, x, in hours:

What is the speed of the motorboat?

35miles per hour
70 miles per hour
105 miles per hour
315 miles per hour

Answer 1

It. B. I. JUST. DID. THE. TEST

Explanation:

Answer 2

Speed can be defined as the ratio of Change in Distance and Change in Time
i.e
Speed = (Change in distance) / (Change in time)

Since the graph is a straight line, we can consider any interval to calculate the speed as for a Linear graph the change remains the same.

From the graph we can see that at 1 hr the distance covered is 105 miles and at 2 hr the distance covered is 175 miles.

Change in Distance = 175 – 105 = 70 miles
Change in time = 2 – 1 = 1 hour

So, the speed is = 70 mile/1 hour = 70 miles per hour.

So option B gives the correct answer