Answer:
6 seconds
Step-by-step explanation:
Initial distance of Mario from motion detector = 2 ft
Speed of Mario = 1.5 ft/sec
Total distance of Mario from motion detector = 11 ft
Total distance moved by Mario while walking at the rate of 1.5 ft/sec = 11 - 2 = 9 ft
Given that:
Distance = 9 ft
Speed = 1.5 ft/sec
Formula:
[tex]Distance = Speed \times Time[/tex]
[tex]\Rightarrow 9 =1.5 \times Time\\\Rightarrow Time = \dfrac{9}{1.5}\\\Rightarrow Time = \bold{6\ sec}[/tex]
So, at 6 seconds, Mario will be 11 ft from the motion detector.