calculating international time

You are referring to longitude, not time. The longitude for Nairobi is 36 degrees east and for Chicago it is 87 degrees west. You need the correct longitude in order to calculate the time correctly.

Time difference =appx (longitude difference /360) x24 hrs.
(add if going east, subtract if going west)

NB. Chicago is 88 degrees West. Nairobi 36 degrees East

thanx guys and true its meant to be longitudes and not time as for the accuracy of the longitudes it not necessary since it was a test I did they just make the quiz creatively to encourage critical thinking I appreciate

The Earth spins at 2 pi radians per 24 hours clockwise. That would be pi/12 radians per hour--or 15 degrees/hr clockwise. So an hour is 15 degrees.

88W to 36E is 124 degrees East--that's eight hours and 16 minutes.

12 noon in Chicago is 8:16 PM (solar) in Nairobe.

Rap