There is a circular pond and there is a road around the pond The road is 4ft wide The area

x=4.9 is ans
12 years agoHelpfull: Yes(8) No(1)
let radius of pond ...a
area of pond = pi*a2
let radius of road from centr of pond is ...b
so area of road is = pi(b2-a2)
acc. to problem
(11/25)(pi*a2)=pi(b2-a2)
so (36/25)a2=b2
(6/5)a=b...........(lenght cant be -ve)
given width of road is 4feet....
b=a+4
so a=20
radius of pond is 20feet
12 years agoHelpfull: Yes(6) No(6)
Road area a= pi(r+4)^2 - pi r^2
pool area b=pi r^2
11/25=a/b
solve the above one & you get the radius of the pond...
12 years agoHelpfull: Yes(3) No(3)
area of pond =1125area of road
pi*x^2=1125(pi*(x+4)^2-pi*x^2)
solve x=1.5
12 years agoHelpfull: Yes(3) No(1)
let radius of pond is r then
radius of road is=(r+4)-r=4
so
r^2/(((r+4)^2))-r^2)=11/25
so,(((r+4)^2))-r^2)/r^2=25/11
applying componendo and dividendo,
((((r+4)^2))-r^2)/r^2)+1=(11/25)+1
((r+4)^2)/r^2=33/11
3*r^2=(r+4)^2
((r+4)^2)-3r^2=0
r+4+underroot3=0
and r+4- underroot3=0
solving,r=4-underroot3 or r=4+underroot 3
12 years agoHelpfull: Yes(2) No(3)
4.26*sqrt{(25*8)/11}
12 years agoHelpfull: Yes(0) No(2)
approx 4.984 let radius of pond be r then radius of bigger circle be r+4
so using r^2=11/25*((r+4)^2-r^2) we get r=4.984
12 years agoHelpfull: Yes(0) No(0)

There is a circular pond and there is a road around the pond. The road is 4ft wide. The area of the pond is 11/25 of the area of the road. What is the radius of the pond?