Question

The below diagram shows a flood warning post in a river. What is the water level shown in the diagram in cm ?

• A. $2$
• B. $-2$
• C. $20$
• D. $-20$

Answer 1

The correct option is D $-20$


In the flood warning post, there are $5$ divisions between $0$ cm mark and $-50$ cm.
$\Rightarrow$ Each division $=\frac{|-50|}{5}=\frac{50}{5}=10$ cm

As shown in the figure, the water level is two divisions below the $0$ cm mark.
$\therefore$ Current water level = $(-10)+(-10)=-20$ cm

Therefore, option (d.) is the correct one.