a circular ground whose diameter is 40 metres , has a garden of area 1100 m ^ 2 around it . what is the wide of the path of the garden ?
"req . area = ï € [ ( 20 ) 2 â € “ ( r ) 2 ] = 22 â  „ 7 ã — ( 400 - r ^ 2 ) [ since a 2 - b 2 = ( a + b ) ( a - b ) ] ie ) 22 / 7 ( 400 - r ^ 2 ) = 1100 , ie ) r ^ 2 = 50 , r = 7.07 m answer b"
subtract(circle_area(add(divide(40, 1100), 1100)), circle_area(divide(40, 1100)))