CBSE Class 9CBSE
Share
Notifications

View all notifications
Books Shortlist
Your shortlist is empty

A Hand Fan is Made by Stitching Lo Equal Size Triangular Strips of Two Different Types of Paper as Shown in Fig. 12.28. - CBSE Class 9 - Mathematics

Login
Create free account


      Forgot password?

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.

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`

∴𝐡𝑦 𝑒𝑠𝑖𝑛𝑔 π»π‘’π‘Ÿπ‘œπ‘›′π‘ π‘“π‘œπ‘Ÿπ‘šπ‘’π‘™π‘Žπ‘’

π΄π‘Ÿπ‘’π‘Ž π‘œπ‘“ (Δ𝐴𝑂𝐡)=`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 ×(π‘Žπ‘Ÿπ‘’π‘Ž π‘œπ‘“ Δ𝐴𝑂𝐡)
= 5 × 168
= `840 cm^2`

 

  Is there an error in this question or solution?

APPEARS IN

Solution A Hand Fan is Made by Stitching Lo Equal Size Triangular Strips of Two Different Types of Paper as Shown in Fig. 12.28. Concept: Area of a Triangle by Heron’S Formula.
S
View in app×