I need help to find the point where the where the equator (0°...

I need help to find the point where the where the equator (0° latitude) intersects the prime meridian (0° longitude). 

60° E longitude and 30° N latitude 

60° W longitude and 30° N latitude  120° E longitude and 30° N latitude 

Correct!

120° W longitude and 30° N latitude 

First find the origin of the geographic coordinate system where the equator (0° latitude) intersects the prime meridian (0° longitude). Next, figure out the spacing of the latitude and longitude grid. Knowing that latitude ranges from 0° to 90° North and South, you should be able to determine that the parallels and meridians are spaced at a 30° interval

Now count the number of meridians from the prime meridian to the target meridian. Multiply that number (4) times the grid spacing (30°). Note that when the globe is oriented “north up,” you are moving west when you move left. The result is the target meridian, 120° W. 

Determine the target latitude in the same way. Count the number of parallels from the equator to the target parallel. Multiply that number (1) times the grid spacing (30°). The result is the target parallel, 30° N.