JAMB Geography 2011 Paper

Concept:Reducing a map’s dimensions by a linear fraction changes the scale denominator by the same dividing factor.Explanation:Original scale is $1:40,000$, meaning 1 unit on the map represents 40,000 units on the ground.When the map is reduced to one quarter of its size, its linear measurements become $\frac{1}{4}$ of the original.Therefore, 1 unit on the new map represents $4 \times 40,000 = 160,000$ ground units.So the new scale is $1:160,000$.Answer:C. $1:160,000$