Question

The data table represents the distance between a well-known lighthouse and a cruise ship over time. The cruise ship is travelling at uniform speed. What will be the distance between the cruise ship and the lighthouse after 5 hours?

Number of Hours

Distance from Lighthouse (in oceanic miles)

2 53
4 95.5
6 138
8 180.5
10 223
12 265.5
14 308
16 350.5

84.50 oceanic miles
89.75 oceanic miles
116.75 oceanic miles
128.50 oceanic miles
223.00 oceanic miles

Answer 1

116.75 oceanic miles

Explanation:

A graph of the data shows the distance to be between 110 and 120 miles (closer to 120). There is only one answer choice in that range.

In 2 hours, the ship travels 42.5 miles, so in 1 hour will travel 21.25 miles. Adding that distance to the distance at 4 hours gives the distance at 5 hours, ...

95.5 +21.25 = 116.75 . . . . "oceanic" miles

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In order for the distance from the lighthouse to be uniformly increasing, the ship must be traveling directly away from the lighthouse. Traveling at any other angle, the distances will not fall on a straight line. (That is one reason I wanted to graph the data.)