Question

A public park, in the form of a square, has an area of $(100\pm 0.2)m^2$ .The side of park is :

• A. $(10\pm 0.01)m$
• B. $(10\pm 0.1)m$
• C. $(10\pm 0.02)m$
• D. $(10\pm 0.2)m$

Answer 1

The correct option is A $(10\pm 0.01)m$

Let the side length of the square park is $l$.

The area of a square is given as,

$A=l^2$

$100=l^2$

$l=10m$

The error in length is given as,

$\frac{\Delta A}{A}=2\frac{\Delta l}{l}$

$\frac{0.2}{100}=2\frac{\Delta l}{10}$

$\Delta l=0.01m$

Thus, the side of the park is $\left(10\pm 0.01\right)m$.