Answer:
It would take you 5/3 hours, or 1 hour and 40 minutes.
Hope I helped! ☺
 
        
             
        
        
        
I FOUND YOUR COMPLETE QUESTION IN OTHER SOURCES.
 SEE ATTACHED IMAGE, PLEASE.
 The first thing we must do for this case is to define variables.
 n = number of 5k races covered
 f = end time.
 We have the following equation:
 f = -1.2n + 38.1
 We note that the slope of the line is:
 m = -1.2 minutes per race
 Therefore, the time decreases 1.2 minutes when the number of races increases n. 
Answer:
 The model predicts that for each additional race to runner has run, the finishing time decreases by about 1.2 minutes
 
        
             
        
        
        
You can count the spirals because they are coloured.
The left handed spirals are in red and you can count 13.
The rifht hanged spirals are in yellow and you can count 21.
Fibonacci sequence is: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... From 2 the next number is the sum of the two previous numbers: 
2 = 1 + 1
3 = 2 + 1
5 = 3 + 2
8 = 5 + 3
13 = 8 + 5
21 = 13 + 8.
Fibonacci numbers are found in many structures in nature.
We have just found that these cacti enclose Fibonacci numbers 13 and 21. 
Answer: 13 and 21