Question

2. A scuba diver was exploring a reef 77.5 m below sea level. The diver ascended to the surface at a rate of 12.5 m/min. (a) Write an equation to model the situation. Use the formula d = rt. (b) Explain why it is reasonable to write the distance, d, as a positive number? Explain. (c) How long did it take the diver to reach the surface?

Answer 1

77.5 = 12.5t

6.2 mins.

Explanation:

The scuba diver was at the sea bed from where the water surface is at 77.5 m height. The ascending speed of the diver is 12.5 m/minute.

a. If the diver take t minutes to reach the water surface, then the equation that models the situation is

77.5 = 12.5t ......(1)

b. If we consider the sea bed as a reference level i.e. zero height, then the sea surface will be at 77.5 m height.

Therefore, in that case, it is reasonable to write the distance 77.5 m as a positive number.

c. Solving the equation (1), we get, t = 6.2 minutes.

So, the diver will take 6.2 mins to reach the surface. (Answer)