Mackenzie is scuba diving off the coast of Hawaii. When she is ready to come back to the surface, she rises at a safe speed of 1 foot every 2 seconds. If her dive was 40 yards deep, how many minutes will it take her to resurface?

Question

Write your answer as a whole number, decimal, or simplified fraction. Do not round.
min

Answer 1

To find out how long it will take Mackenzie to resurface, we first need to convert the depth of her dive from yards to feet, then determine her ascent rate and calculate the time taken.

1. Convert yards to feet:
   There are 3 feet in 1 yard, so: \[ 40 \text{ yards} = 40 \times 3 = 120 \text{ feet} \]

2. Determine her ascent rate:
   Mackenzie rises at a rate of 1 foot every 2 seconds.

3. Calculate the total time taken to rise:
   To find the total time in seconds to rise from 120 feet: \[ \text{Time} = \text{Depth} \times \text{Time per foot} = 120 \text{ feet} \times 2 \text{ seconds per foot} = 240 \text{ seconds} \]

4. Convert seconds to minutes:
   There are 60 seconds in 1 minute, so: \[ \text{Time in minutes} = \frac{240 \text{ seconds}}{60 \text{ seconds per minute}} = 4 \text{ minutes} \]

Therefore, it will take Mackenzie 4 minutes to resurface.