Advertisements
Advertisements
Question
The circumference of a circle exceeds its diameter by 18 cm. find the radius of the circle.
Advertisements
Solution
Let c be the circumference and d be the diameter of the circle.
∴ c = d + 18
⇒ dπ = d + 18 ⇒ dπ − d = 18
d(π − 1) = 18
⇒ `"d"(22/7-1)` = 18
⇒ `"d"(15/7) =18`
⇒ d =`(18xx7)/15=126/15` = 8.4 cm
∴ Radius =`"d"/2=8.4/2` = 4.2 cm
APPEARS IN
RELATED QUESTIONS
The area of a rhombus is 480 cm2, and one of its diagonals measures 48 cm. Find
(i) the length of the other diagonal,
(ii) the length of each of its sides, and
(iii) its perimeter.
In the given figure, APB and AQO are semicircles and AO = OB. If the perimeter of the figure is 40 cm, find the area of the shaded region.

The wheels of the locomotive of a train are 2.1 m in radius. They make 75 revolutions in one minute. Find the speed of the train in km per hour.
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.
Sum of the areas of two squares is 157 m2. If the sum of their perimeters is 68 m, find the sides of the two squares.
The radius of a circular garden is 56 m. What would it cost to put a 4-round fence around this garden at a rate of 40 rupees per metre?
The diameter of a circle is 5.6 cm. Find its circumference.
Find the circumference of the circles whose radii are given below.
49 cm
Value of π is ______ approximately.
A circle with radius 16 cm is cut into four equal parts and rearranged to form another shape as shown in the following figure:

Does the perimeter change? If it does change, by how much does it increase or decrease?
