Elitmus
Exam
Numerical Ability
Arithmetic
A park is in the shape of concentric circle. Milkha Singh runs from one point on the outer circle to the other opposite point of the outer circle such that it touches the inner circle at only one point. The distance travelled by him so is 24 metres. Then find the area inside the outer cirlce but outside the inner circle.
Read Solution (Total 3)
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- 24 cm is a chord & perendicular drawn from centre bisects it
R^2 = r^2 + 12^2
reqd area = pi * ( R^2 - r^2 ) = pi *(r^2 + 144 - r^2) = 144*pi m^2
- 10 years agoHelpfull: Yes(24) No(1)
- Milkha singh is running from one point on the outer circle to the other point while touching the inner circle only once this means this will form a chord to the inner circle
Now if we draw a perpendicular from the center then it will divide the chord into 2 equal parts now with the help of pythagoras triplets r will become 9 and R will become 15 so the required area will be given by pi*(R^2-r^2)
Pi*(15^2-9^2)=pi*144 Sq metre - 10 years agoHelpfull: Yes(1) No(1)
- Area Of a Circle= pi*r*r
Here there are Two Circle 1)Outer Circle 2)Inner Circle
Given the diameter of Outer Circle which Includes Inner Circle also .SO D= 24m ,Therefore r=12m(Outer), Inner(6m) ..So The Reqd Area= Pi*6*6 Respectively !! - 10 years agoHelpfull: Yes(0) No(4)
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