Question

7. If a wire of 440 m length is moulded in the form
find the ratio of the area of the circle to that of square. ?
8. Find the area of the square that can be inscribed in a cir
9. The diameter of a circular park is 24 m. A 3 m wide path
runs around it from inside. Find the cost of paving the
path at * 25 per square meter.
10. A paper is in the form of a rectangle PQRS in which
PQ = 10 cm and QR = 7 cm. Two semi-circular portions
with QR and PS as diameters are cut off (As shown in
figure 11.22). Find the area of the remaining part.​

Answer 1

Answer:

Given

2πr=440

4a=440

find

ratio of →  

areaofsquare

areaofcircle

​  

 

sol

2πr=440

r=  

2π

440

​  

=  

π

220

​  

 

circle (Area) = πr  

2

 

=π×  

π

220

​  

×  

π

220

​  

 

⇒  

π

(220)  

2

 

​  

 

4a=440

a=110

Area sq = a  

2

 

=110×110

∴ Ratio =  

π×110×110

220×220

​  

 

⇒  

π

4

​  

  [∵π=  

7

22

​  

]

⇒  

22

4

⇒  

22

4

​  

×7=  

22

28

​