Advertisements
Advertisements
प्रश्न
The sum of the radii of two circles is 10.5 cm and the difference of their circumferences is 13.2 cm. Find the radii of the two circles.
Advertisements
उत्तर
Let r1 and r2 be the radii of two circles.
⇒ r1 + r2 = 10.5 ....(i)
And,
`2π"r"_(6.3-4.21) - 2π"r"_2` = 13.2
⇒ `2 xx (22)/(7) xx ("r"_1 - "r"_2)` = 13.2
⇒ r1 - r2 = `(13.2 xx 7)/(2 xx 22)`
⇒ r1 - r2 = 2.1 ....(ii)
Adding (i) and (ii), we get
2r1 = 12.6
⇒ r1 = 6.3cm
Now,
r1 - r2 = 2.1
⇒ 6.3 - r2 = 2.1
⇒ r2 = 4.2cm.
APPEARS IN
संबंधित प्रश्न
A 36-m-long, 15-m-borad verandah is to be paved with stones, each measuring 6dm by 5 dm. How many stones will be required?
From each of the two opposite corners of a square of side 8 cm, a quadrant of a circle of radius 1.4 cm is cut. Another circle of radius 4.2 cm is also cut from the centre as shown in the following figure. Find the area of the remaining (Shaded) portion of the square. (Use π = 22/7)
In the following figure, ABCD is a rectangle, having AB = 20 cm and BC = 14 cm. Two sectors of 180° have been cut off. Calculate:
the area of the shaded region.
If the radius of a circle is diminished by 10%, then its area is diminished by
In the following figure, the shaded area is
ABCD is a rectangle whose three vertices are B (4,0), C (4,3) and D (0, 3). The length of one of its diagonals is
The radius of a wheel is 0.25 m. How many revolutions will it make in covering 11 km?
A square is inscribed in a circle of radius 6 cm. Find the area of the square. Give your answer correct to two decimal places if `sqrt(2)` = 1.414.
Find the area of the biggest circle that can be cut from a rectangular piece 44cm by 28cm. also, find the area of the paper left after cutting out the circle.
The length of the minute hand of a clock is 14 cm. The area swept by the minute hand in 5 minutes is ______.
