Google says that 1 mile = 5280 feet.
So if the gocart would go at 5280 feet per hour, it would go at 1 mile per hour.
And if the gocart would go at (2*5280) feet per hour, it would go at 2 mile per hour.
607200 / 5280 = 115, so the top speed is 115 mph.
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It helps a lot if you keep the dimensions during calculation when solving physics exercises.
Just use them as joker numbers or variables as whole and keep them everytime. Don't forget them.
1 mile = 5280 feet. just like 1 * mile = 5280 * feet
Divide by 5280
1/5280 mile = 1 feet, so feet = 1/5280 mile
Top speed is 607200 feet / hour
Substitute feet with the thing above we just found out.
Top speed = 607200 feet / hour = 607200 ( 1/5280 mile) / hour = 607200/5280 mile/hour = 115 mile/hour = 115 mph.
If you use the dimensions correctly, they help checking yourself.
Good luck!
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