Question

Earth is covered 70% with water and the rest by land. If 20% of the Southern Hemisphere is land, then what is the ratio of land to water in the Northern Hemisphere?

• A. 1:3
• B. 3:1
• C. 2:3
• D. 3:2

Answer 1

The correct option is C 2:3

Land:Water on Earth = 3:7
Land:Water in the Southern Hemisphere = 2:8 = 1:4
Let’s say that $100m^2$ of the total area:
$30m^2$ land, $70m^2$ water.

Southern Hemisphere:
The Southern Hemisphere is half Earth’s surface area = $50m^2$
Land in the Southern Hemisphere = $10m^2$
Water in the Southern Hemisphere = $40m^2$

Northern Hemisphere:
Remaining land = $30-10=20m^2$
Remaining water = $70-40=30m^2$
Ratio = 2:3 in the Northern Hemisphere