A horse is tied to a peg at one corner of a square shaped grass field of side 15 m by means of a 5 m long rope (see figure). Find the increase in the grazing area if the rope were 10 m long instead of 5 m. (Use $\pi = 3.14$)
"

AcademicMathematicsNCERTClass 10

Given: 

A horse is tied to a peg at one corner of a square shaped grass field of side $15\ m$ by means of a $5\ m$ long rope.

To do: 

We have to find the increase in the grazing area if the rope were 10 m long instead of 5 m.

Solution: 

Length of the rope is increased from $5\ m$ to $10\ m$

This implies,

New radius of the sector grazed by the horse $= 10\ m$

Therefore,

Area grazed by the horse$=$ Area of the quadrant $( 10\ m)$

$=\frac{1}{4}\pi r^2$

$=\frac{1}{4}\times3.14\times(10)^2$

$=25\times3.14$

$=78.5\ m^2$

This implies,

Increase in the grazing area $=78.5-19.625$

$=58.875\ m^2$

Therefore, increase in the grazing area is $58.875\ m^2$.

raja
Updated on 10-Oct-2022 13:23:56

Advertisements