Can someone explain why this

https://i.imgsafe.org/b4b5bd1e19.png

couldn't be simplified to this

80 miles/3600 sec x 1609 meters/1 mile

When I tried to simplify the conversion steps to this I got

128,720 meters/60 second=2,145

But the correct answer is 36 mps

I'm not sure why it didn't work

Question

Can someone explain why this 

https://i.imgsafe.org/b4b5bd1e19.png

couldn't be simplified to this 

80 miles/3600 sec x 1609 meters/1 mile

When I tried to simplify the conversion steps to this I got 

128,720 meters/60 second=2,145 

But the correct answer is 36 mps

I'm not sure why it didn't work

kikuo · Answer

I don't understand why we couldn't shorten the long string to what I had and get the right answer. 

Can someone explain?

karim728 · Answer

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