Advertisements
Advertisements
Question
A dinner plate is in the form of circle. A circular region encloses a beautiful design as shown in the following figure. The inner circumference is 352 mm and outer is 396 mm. Find the width of circular design.

Advertisements
Solution
Let the radius of inner and outer circle be r and R, respectively.
Given, inner circumference = 352 mm
⇒ 2πr = 352 ...[∵ Circumference = 2πr]
⇒ `2 xx 22/7 xx r = 352`
⇒ `r = (352 xx 7)/(2 xx 22) = 2464/44` = 56 mm
And outer circumference = 396 mm ...[Given]
⇒ 2πr = 396
⇒ `2 xx 22/7 xx R = 396`
⇒ R = `(396 xx 7)/(2 xx 22)` = 63 mm
∴ Width of circular design = R – r = 63 – 56 = 7 mm
APPEARS IN
RELATED QUESTIONS
The radii of two circles are 8 cm and 6 cm respectively. Find the radius of the circle having area equal to the sum of the areas of the two circles.
A horse is placed for grazing inside a rectangular field 40m by 36m and is tethered to one corner by a rope 14m long. Over how much area can it graze.
In a circle of radius 10.5 cm, the minor arc is one-fifth of the major arc. Find the area of the sector corresponding to the major arc.
Find the area and perimeter of the circle with the following :
Diameter = 77 cm
A 7 m road surrounds a circular garden whose area is 5544 m2. Find the area of the road and the cost of tarring it at the rate of Rs.150 per sq m.
A circus tent is cylindrical to a height of 5 m and conical above it. If its diameter is 42 m and slant height of the cone is 53 m, calculate the total area of the canvas required.
The radius of a circle is 21 cm. Find the circumference (Take π = `3 1/7`).
A race track is in the form of a circular ring whose outer and inner circumferences are 396 m and 352 m respectively. The width of the track is ____________.
Area of circular garden with diameter 8 m is ______.
The distance around a circle is its ______.
