Cairo is 3.75 hours behind Kathmandu
Best overlap: 11:45 AM to 6:45 PM in Kathmandu is 8:00 AM to 3:00 PM in Cairo.
If you set up a recurring sync, 11:45 AM to 6:45 PM in Kathmandu (8:00 AM to 3:00 PM in Cairo) is the natural home for it. Cairo is 3.75 hours behind Kathmandu, but you still share a generous 7 hours of overlap, so scheduling is easy and there's room to move a meeting when you need to. Remember that Cairo shifts for daylight saving and Kathmandu doesn't, so recalculate the overlap after each clock change.