Advertisements
Advertisements
Question
Find the area of Fig. 20.25, in square cm, correct to one place of decimal. (Take π = 22/7)
Advertisements
Solution
The given figure is:
Construction : Connect A to D.
Then, we have: Area of the given figure = (Area of rectangle ABCD + Area of the semicircle) - (Area of ∆ AED).
∴ Total area of the figure = (Area of rectangle with sides 10 cm and 10 cm) + (Area of semicircle with radius\[ = \frac{10}{2} = 5 cm)\] - (Area of triangle AED with base 6 cm and height 8 cm)
\[ = (10 \times 10) + (\frac{1}{2} \times \frac{22}{7} \times 5^2 ) - (\frac{1}{2} \times 6 \times 8)\]
\[ = 100 + 39 . 3 - 24\]
\[ = 115 . 3 {cm}^2\]
RELATED QUESTIONS
A flooring tile has the shape of a parallelogram whose base is 24 cm and the corresponding height is 10 cm. How many such tiles are required to cover a floor of area 1080 m2? (If required you can split the tiles in whatever way you want to fill up the corners).
An ant is moving around a few food pieces of different shapes scattered on the floor. For which food − piece would the ant have to take a longer round? Remember, circumference of a circle can be obtained by using the expression c = 2πr, where r is the radius of the circle.
A playground has the shape of a rectangle, with two semi-circles on its smaller sides as diameters, added to its outside. If the sides of the rectangle are 36 m and 24.5 m, find the area of the playground. (Take π = 22/7).
The inside perimeter of a running track (shown in Fig. 20.24) is 400 m. The length of each of the straight portion is 90 m and the ends are semi-circles. If track is everywhere 14 m wide, find the area of the track. Also, find the length of the outer running track.
The length and breadth of the rectangular piece of land area in the ratio of 5 : 3. If the total cost of fencing it at the rate of ₹48 per metre is ₹19,200, find its length and breadth.
The area of a parallelogram is 60 cm2 and one of its altitudes is 5 cm. The length of its corresponding side is ______.
Mukesh walks around a circular track of radius 14 m with a speed of 4 km/hr. If he takes 20 rounds of the track, for how long does he walk?
The length of an aluminium strip is 40 cm. If the lengths in cm are measured in natural numbers, write the measurement of all the possible rectangular frames which can be made out of it. (For example, a rectangular frame with 15 cm length and 5 cm breadth can be made from this strip.)
Which branch of mathematics deals with the measurement of length, area, volume, and surface area of geometric figures?
Which of the following is an example of a closed figure?
