The scuba diver must descend 3 feet in the fifth minute to meet the goal.
Why?
To find how many feet does the scuba diver need to descend to reach the goal of 35 feet in 5 minutes, we need to calculate how many feet he did descend on the first 4 minutes.
So, calculating we have:
[tex]FirstMinute=9ft\\SecondMinute=11ft\\ThirdMinute=5ft\\FourthMinute=7ft\\Total=9ft+11ft+5ft+7ft=32ft\\\\Goal=35ft\\\\Needed=Goal-Total(4Minutes)\\\\Needed=35ft-32ft=3ft[/tex]
Hence, we can see that at the 4 minute, he has only descended 32ft. It means that he need to descend 3 feet more in the fifth minute.
Have a nice day!
