Question

Mario is walking away from a motion detector at a rate of 1.5 feet per second. He started recording his distance from the motion detector when he was 2 feet in front of the motion detector. Fill in the blank in the sentence below. Mario is 11 feet from the motion detector at ____ a seconds

Answer 1

6 seconds

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:

`Distance = Speed * Time`

`\Rightarrow 9 =1.5 * Time\\\Rightarrow Time = (9)/(1.5)\\\Rightarrow Time = \bold{6\ sec}`

So, at 6 seconds, Mario will be 11 ft from the motion detector.