A scuba diver is 30 feet below the surface of the water 10 seconds after he entered the water and 100 feet below the surface after 40 seconds. What is the scuba diver's rate of change? Round to the nearest tenth.

2.3 feet / second

Step-by-step explanation:

To find the rate of change, we will have to find the difference in his distance travelled and divide it by the time taken to move that distance.

This is given by rate of change = (change in position) / change in time

From the question, his position changed from 30 ft to 100 ft thus the distance he travelled is = 100ft - 30 ft = 70 ft.

Time taken to travel this distance = 40 seconds - 10 seconds = 30 seconds

Diver's rate of travel = 70 ft / 30 seconds = 2.33333ft/second.

Rounding off the answer to the nearest tenth, we have 2.3 ft/second