I guess fps stands for feet per second. Divide that number by whatever the number of feet there is in a mile, to convert to miles per second. Then multiply the result by 3600 to convert from "per second" to "per hour".
156 mph is 251.058 kmph
228 kmph is 141.673 mph
207 kmph is 128.624 mph
290 kmph is 180.198 mph
Remember that there are more KMPH than there is in MPH. One KMPH = nearly .61 MPH, so 61 MPH = 100 KMPH so 150 MPH should = roughly 241.5 KMPH.
75 mph = 120.7008 kmph 60 mph= aprox 100 kmph
51.499 kmph
3 mph = 4.83 kmph
156.4 kMPH is ~97.2 MPH
1 mile = 1.6 km Hence 143 kmph = 89.375 mph
To convert mph to kmph, 1.61. For kmph to mph, 0.62
about 2.3 mph