The time he spent running is 13.80 seconds.
The equation that can be used to represent the time he gets to the tree is:
Time he gets to the tree = (time of each spin x total spins) + time he spent running
21 = (6 x 1.2) + r
21 = 7.20 + r
r = 21 - 7.20
r = 13.80 seconds
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