Advertisements
Advertisements
Question
A hand fan is made by stitching lo equal size triangular strips of two different types of paper as shown in Fig. 12.28. The dimensions of equal strips are 25 cm, 25 cm and 14 cm. Find the area of each type of paper needed to make the hand fan.
Advertisements
Solution
Given that the sides of ΔAOB are
AO = 24 cm
OB = 25 cm
BA = 14 cm
Area of each equal strips = Area of Δle AOB
Now, for area of ΔAOB
Perimeter of ΔAOB
Let 2s = AO + OB + BA
`⇒s=1/2(AO+OB+BA)`
`=1/2(25-25-14)=32 cm`
∴๐ต๐ฆ ๐ข๐ ๐๐๐ ๐ป๐๐๐๐′๐ ๐๐๐๐๐ข๐๐๐
๐ด๐๐๐ ๐๐ (Δ๐ด๐๐ต)=`sqrt(s(s-ao(s-ob)s-ba))`
`=sqrt(32(32-25)(32-25)(32-14))`
`=sqrt(32(7)(4)(18))`
`=168 cm^2`
∴ Area of each type of paper needed to make the hand fan = 5 ×(๐๐๐๐ ๐๐ Δ๐ด๐๐ต)
= 5 × 168
= `840 cm^2`
APPEARS IN
RELATED QUESTIONS
The triangular side walls of a flyover have been used for advertisements. The sides of the walls are 122m, 22m, and 120m (see the given figure). The advertisements yield an earning of โน 5000 per m2 per year. A company hired one of its walls for 3 months. How much rent did it pay?
The perimeter of a triangle is 300 m. If its sides are in the ratio 3 : 5 : 7. Find the area of the triangle ?
Find the area of the shaded region in the given figure.
A triangle and a parallelogram have the same base and the same area. If the sides of the triangle are 13 cm, 14 cm and 15 cm and the parallelogram stands on the base 14 cm, find the height of the parallelogram.
Find the area of the triangle formed by the points
(1, – 1), (– 4, 6) and (– 3, – 5)
Determine whether the sets of points are collinear?
(a, b + c), (b, c + a) and (c, a + b)
An advertisement board is in the form of an isosceles triangle with perimeter 36 m and each of the equal sides are 13 m. Find the cost of painting it at โน 17.50 per square metre.
Find the area of a parallelogram given in figure. Also find the length of the altitude from vertex A on the side DC.
How much paper of each shade is needed to make a kite given in the following figure, in which ABCD is a square with diagonal 44 cm.
The perimeter of a triangle is 50 cm. One side of a triangle is 4 cm longer than the smaller side and the third side is 6 cm less than twice the smaller side. Find the area of the triangle.
