I would like to give a question which
i could not solve.Rd sharma class 10
maths exercise-15.4 mensuration.
In this question we have to find the cost
of turfing the plot at Rs 1.25 per square
meter given that a square tank has its side
equal to 40 m. There are four semi-circular
grassy plots all around it.
Given,
Side of the square tank = 40 m
And, the diameter of the semi-circular grassy plot = side of the square tank = 40 m
Radius of the grassy plot = 40/2 = 20 m
Then,
The area of the four semi-circular grassy plots = 4 x ½ πr2
= 4 x ½ (3.14)(20)2
= 2512 m2
Rate of turfing the plot = Rs 1.25 per m2
So, the cost for 2512 m2 = (1.25 x 2512) = Rs 3140