Question

A map has a scale of 5 : 20,000. A distance of 30 units on the map is equivalent to ____ units in real.

• A. 90,000
• B. 1,20,000
• C. 1,10,000
• D. 80,000

Answer 1

The correct option is B 1,20,000

Scale of the map is 5 : 20,000.​

This means that 5 units on the map represents 20,000 units in real.​

Clearly, as the distance in real increases, corresponding distance on map increases.​

So, distance in real a distance on map​

Let distance in real be ‘r’ and distance on map be ‘m’​

Then, r is directly proportional to m​

Therefore,​

$\frac{r_1}{m_1}=\frac{r_2}{m_2}$

Given​

$r_1=$20,000 units​

$m_1=$ 5 units​

$r_2=$ distance in real​

$m_2=$ 30 units​

Putting the values in $\frac{r_1}{m_1}=\frac{r_2}{m_2}$

=$\frac{20,000}{5}=\frac{r_2}{30}$

Hence, distance in real, $r_2=\frac{(20,000\times 30)}{5}=1,20,000$ units​

​Answer: (C) 1,20,000​