Question

A running track is enclosed between two concentric circles of radii 40 m and 37 m. Find the area of the running track.

Answer 1

Answer:

Step-by-step explanation:

Take R = 40 cm which is radius of outer circle

and r = 38 cm which is radius of inner circle

To find the area of the track we can use the formula :

( 2 pie R ^2 ) - ( 2 pie r ^2 ) => 2 pie ( R ^2 - r ^ 2) => 2× 3.14 ( 40^2 - 38^ 2)

=> 6.28 ( 1600 - 1444 )

=> 6.28 × 156

=> 979.68 cm square

Answer 2

Take R = 40 cm which is radius of outer circle

and r = 38 cm which is radius of inner circle

To find the area of the track we can use the formula :

( 2 pie R ^2 ) - ( 2 pie r ^2 ) => 2 pie ( R ^2 - r ^ 2) => 2× 3.14 ( 40^2 - 38^ 2)

=> 6.28 ( 1600 - 1444 )

=> 6.28 × 156

=> 979.68 cm square