If parallels of latitude are drawn on a globe at an interval of 1 degree, how many parallels will there be, including the Equator (and treating the poles as points, not lines)?

If parallels are drawn at every 1 degree, there are 89 parallels in the Northern Hemisphere (1 to 89 degrees North), 89 in the Southern Hemisphere (1 to 89 degrees South), and the Equator. So, the total is 89 + 89 + 1 = 179.

Why the poles are not counted:

• The North Pole (90 degrees North) and the South Pole (90 degrees South) are single points, not circles.
• So, they are not counted as parallels of latitude.

If the poles were counted:

Some textbooks count the poles as well, giving 181 "latitudes" (0 to 90 degrees North and South). The question here specifies the count of parallels including the Equator, which gives 179.

What latitude is:

• Latitude is the angular distance of a place north or south of the Equator, measured from the centre of the Earth.
• It ranges from 0 degrees at the Equator to 90 degrees at the poles.
• Lines of latitude are called parallels because they are parallel to each other and never meet.

Meridians of longitude:

• Meridians are drawn from pole to pole.
• At an interval of 1 degree, there are 360 meridians: 0 degrees (the Prime Meridian), 1 to 179 degrees East, 1 to 179 degrees West, and 180 degrees.
• The 180 degree meridian is shared by the East and West, so the total is 1 + 179 + 179 + 1 = 360.
• Unlike parallels, all meridians are equal in length; each is half a great circle.

Grid of the Earth:

The network of parallels and meridians on a globe or map is called a graticule.

Why not the other options?

• ✗180 and 181 include one or both poles, which are points rather than parallels.
• ✗360 is the number of meridians at 1 degree intervals, not parallels.