Question 27
HardOriginal questionA sector of a circle of radius 14 cm has a perimeter of 50 cm (two radii plus the arc). What is the area of the sector? Take .
Show the answer and explanation
CorrectNot quiteAnswer A
Correct answer: A
Explanation
Arc length = cm.
The full circumference is cm, so the sector is = ¼ of the circle.
Area = cm². (Shortcut: area = ½ × arc × radius = .)
Worth noting
350 cm² puts the whole perimeter, 50 cm, into ½ × arc × radius. Only the curved part is the arc.
- Concept
- Sector area = ½ × arc length × radius
- Typical timeTypical
- 115 s
- Your timeYours
- —
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