Cindy is running a 400 meter race. she finished with a personal record of 55 seconds. calculate her speed in meters per minute, meters per seconds, and miles per hour. (show work! )

If she has put up a personal record in 55 seconds this means that 400/55 metres per second is her speed.

But if we convert this speed in to meters per minute we can see that we will have to multiply it by 60 as one minute equals to 60 seconds so it will become 436 metres per minute.

And again to convert it into miles per hour we will divide the speed in meters / minutes by 1609 and then multiply by by 60

6e14 is the answer.