Answer:
Average speed = 1 m/s
Explanation:
Given that,
Ohnny walks 900 meters to the store to buy a candy bar. He then walks back home. It would mean that the total distance covered by him is 900 m + 900 m = 1800 m
His total trip took him 30 minutes or 1800 seconds
We need to find the average speed. It is equal to the total distance divided by the total time taken. So,
[tex]v=\dfrac{1800\ m}{1800\ s}\\\\v=1\ m/s[/tex]
So, his average speed is 1 m/s.