The distance of one degree of longitude is equal to?

It's confusing because degrees of longitude are very different from degrees of latitude. Latitude is north or south of the equator and the length of a degree is 1/360 of the circumference no matter what. Longitude lines are all the same length, but a degree means you move from one line to another, and the distance between them depends on where you are. At the equator, one degree is 1/360 of the circumference, but at Θ degrees latitude, one degree of longitude is cos(Θ) times that. Here is a calculator:
www.csgnetwork.com/degreelenllavcalc.html