Question

(b) The ratio of the length of an arc of a circle and the circumference of is given as 2:5. If the radius of the circle is 7 cm, calculate, correct to or decimal place, i. the length of the arc ii. the area of the minor sector​

Answer 1

This means that the central angle of the sector is
`(2/5)(360)=144^(\circ)`

Part i

`(144)/(360) (\pi)(2)(7)=(28\pi)/(5) \text{ cm}`

Part ii

`(\pi)(7^2) (144)/(360)=(98\pi)/(5) \text{ cm}^2`