Answer :
To find this you need to divide 420 by 7. This gives you 60. So the rate is 60 mph (miles per hour).
normallly people want miles per hour or miles/hour
so divvided 420 by 7 =420/7=60/1=60 miles per hour
so divvided 420 by 7 =420/7=60/1=60 miles per hour