Advertisements
Advertisements
प्रश्न
Area of a rectangle and the area of a circle are equal. If the dimensions of the rectangle are 14 cm × 11 cm, then radius of the circle is ______.
विकल्प
21 cm
10.5 cm
14 cm
7 cm
Advertisements
उत्तर
Area of a rectangle and the area of a circle are equal. If the dimensions of the rectangle are 14 cm × 11 cm, then radius of the circle is 7 cm.
Explanation:
Given, dimensions of rectangle, l = 14 cm and b = 11 cm
According to the question,
Area of rectangle = Area of circle
⇒ l × b = πr2
⇒ `14 xx 11 = 22/7 xx r^2`
⇒ `r^2 = (14 xx 11 xx 7)/22` ...`[∵ π = 22/7]`
⇒ r2 = 49
⇒ r = `sqrt(49)`
⇒ r = 7 cm
Hence, the radius of circle is 7 cm.
APPEARS IN
संबंधित प्रश्न
A path of width 3.5 m runs around a semi-circular grassy plot whose perimeter is 72 m . Find the area of the path .
`("Use" pi= 22/7) `
In the following figure, the square ABCD is divided into five equal parts, all having same area. The central part is circular and the lines AE, GC, BF and HD lie along the diagonals AC and BD of the square. If AB = 22 cm, find:
the perimeter of the part ABEF.
Find the area of the shaded region in the following figure, if AC = 24 cm, BC = 10 cm and O is the centre of the circle. (Use π = 3.14)
What is the angle subtended at the centre of a circle of radius 6 cm by an arc of length 3 π cm?
Find the area of the largest triangle that can be inscribed in a semi-circle of radius runits.
If the difference between the circumference and radius of a circle is 37 cm, then using π = \[\frac{22}{7}\] the circumference (in cm) of the circle is
If the radius of a circle is diminished by 10%, then its area is diminished by
The minute hand of a clock is 8 cm long. Find the area swept by the minute hand between 8.30 a.m. and 9.05 a.m.
The diameters of three circles are in the ratio 3: 5: 6. If the sum of the circumferences of these circles is 308 cm; find the difference between the areas of the largest and the smallest of these circles.
Find the area enclosed between two concentric circles of radii 6.3cm and 8.4cm. A third concentric circle is drawn outside the 8.4cm circle. So that the area enclosed between it and the 8.4cm circle is the same as that between the two inner circles. Find the radii of the third circle correct to two decimal places.
