At a distance 5 miles west of town, oil-bearing deposits are found 3187 feet deep. Also, 8 miles west of town, the oil is found 3382 feet down. Assuming the oil-bearing stratum lies on a straight line,
How deep would you expect to drill 10 miles west of town in order to find oil?
A) 3317 feet
B) 3317.95 feet
C) 3512.38 feet
D) 3512 feet

Question

Quizplus · Accepted Answer

The depth of the oil-bearing stratum increases linearly as you move west. The slope of the line can be calculated using the two given points: (5, 3187) and (8, 3382). The slope is (3382 - 3187) / (8 - 5) = 65. Using the point-slope form of a line, the equation is depth = 65(x - 5) + 3187. Plugging in x = 10, the depth is 3512 feet.

At a Distance 5 Miles West of Town, Oil-Bearing Deposits