Simple arithmetic, Anonymous.
100 km/h is equal to 27.77 (repeating) mps.
That's equal to 62.137 mph.
The speed limit on some interstate highways is roughly 100 km/h. (a) What is this in meters per second? (b) How many miles per hour is this?
Just a comment---
It is sometimes convenient to memorize the # of feet per second or a typical highway speed for the purpose of perspective at a moment's notice..
For example, a typical speed in the USA is 60 miles per hour. That converts to 88 feet / second.