Question
The area of a circle is 1.54 cm2. Find the perimeter of the minor sector that is subtended by an angle of 90o. (take Ο = 22/7)
Solution
Area of circle = Ο X radius2
So, 1.54 = (22/7) X radius2
So, 0.49 = radius2
So, radius = 0.7 cm (Since radius cannot be negative, we may discard the negative value of root)
Perimeter of sector = 2 X radius of the circle + length of the arc
Length of minor arc = (ΞΈ/360o) X 2 X Ο X radius
So, length of the minor arc of the given circle = (90o/360o) X 2 X (22/7) X 0.7 = 1.1 cm
So, perimeter of the sector = 1.1 + (2 X 0.7) = 2.5 cm
More Mensuration Questions
- If the area of a triangle is 1080 cm2 and base: corresponding altitude is 3:5, then the altitude of the triangle is:
- If the length of a rectangle becomes double and its breadth becomes three-fourth, then find the percentage increase in its area.
- The length of a rectangle is 3 metres more than its width. If the perimeter of the rectangle is 70 metres then what is the area (in m2Β ) of the rectangle?
- Perimeter of a square is equal to perimeter of a rectangle, if area of square is 576 cm2 and length of rectangle is two times that of breadth. Find the are...
- Consider a rectangle with length 25 cm and breadth 15 cm. If the length is increased by 10% and the breadth is decreased by 40%, determine the perimeter of...
- The circumference of a circle is equal to the perimeter of a rectangle whose length and breadth are in ratio 5:3, respectively. If the area of the rectangl...
- The length, breadth and height of a solid cuboidal box are in the ratio 7 : 5 : 3 and its total surface area is 11502cm2. Its breadth is:
- If the length of a rectangle is increased by 40% and its breadth is decreased by 25%, then the area of the rectangle will be increased or decreased by how ...
- When the ratio of the length and breadth of the rectangle is given as 3:2. If the perimeter of the rectangle is equal to the perimeter of the square, whose...
- The sides of a triangle are in the ratio 5:7:12, and its perimeter is 144 cm. What is the difference in length between the longest and the shortest side?
Relevant for Exams:
