Advertisements
Advertisements
Question
The area of a circle is 1386 sq.cm; find its circumference.
Advertisements
Solution
Area of circle = 1386 cm2
πr2 = 1386
`22/7r^2 = 1386`
`r^2 = 1386 xx 7/22`
`r^2 = 441`
r = `sqrt(441)`
r = 21 cm
circumference = `2pir`
= `2 xx 22/7 xx 21`
= 132 cm
APPEARS IN
RELATED QUESTIONS
A room 4.9 m long and 3.5 m board is covered with carpet, leaving an uncovered margin of 25 cm all around the room. If the breadth of the carpet is 80 cm, find its cost at ₹ 80 per metre.
If the circumference of two circles are in the ratio 2 : 3, what is the ratio of their areas?
The circumference of a circle is 100 m. The side of a square inscribed in the circle is
If diameter of a circle is increased by 40%, then its area increase by
The radius of a circle is 20 cm. It is divided into four parts of equal area by drawing three concentric circles inside it. Then, the radius of the largest of three concentric circles drawn is
A circular disc of radius 6 cm is divided into three sectors with central angles 90°, 120° and 150°. What part of the whole circle is the sector with central angle 150°? Also, calculate the ratio of the areas of the three sectors.
A 7m wide road surrounds a circular garden whose area is 5544m2. Find the area of the road and the cost of tarring it at the rate of Rs.150 per m2.
Area of circle of radius ‘n’ units is
On a square cardboard sheet of area 784 cm2, four congruent circular plates of maximum size are placed such that each circular plate touches the other two plates and each side of the square sheet is tangent to two circular plates. Find the area of the square sheet not covered by the circular plates.
Find the area of the shaded region:
