Question

A water well drilling rig has dug to a height of -15 feet in three hours. If the rig has been running constantly and is currently at a height of -192.5 feet, for how long has the rig been running?

22.25 hours

97.4 hours

38.5 hours

12.8 hours

Answer 1

The drilling rig has been running for 41.5 hours.

Step-by-step explanation:

To determine how long the rig has been running, we need to find the time it took for the rig to drill the additional depth of 192.5 - (-15) = 207.5 feet.

The rig drilled 15 feet in 3 hours, so the rig drills at a rate of 15/3 = 5 feet per hour.

Therefore, the rig has been running for 207.5/5 = 41.5 hours.