Question

how many longitudes can be drawn on a world map keeping an interval of 1 Degree each

Answer 1

The total number of longitudes drawn on world map will be from zero to 359°
the 360° and 0° longitude coincide 
so we can say there are 360 longitudes

Answer 2

Longitudes are important part of geographical studies. Actually the longitudes distance measured in degrees east or west of an imaginary line that is drawn on the surface of the Earth which connects the North and South Pole.

With the help of the longitudinal distance is we can easily locate any point on the earth surface.

The lowest value of this longitude is zero degree and the highest value of the longitudinal degree is 360 degree but we can draw only 360 longitudinal lines at an interval of 1 Degree. Because the zero degree at the 360 degree longitude are collided on each other.