(i) Let ABC be a conical tent.
Height (h) of conical tent = 10 m
Radius (r) of conical tent = 24 m
Let the slant height of the tent be l.
In \(∆\)ABO, AB2 = AO2 + BO2
l2 = h2 + r2
= (10 m)2 + (24 m)2
I= \(\sqrt{676}\)
= 26 m
Therefore, the slant height of the tent is 26 m.
(ii) curved surface area of the cone = \(\pi rl\)
= \(\frac{22}{7}\) × 24 m × 26 m
= \(\frac{13728}{7}\)m²
The cost of the canvas required to make the tent, at \(₹\) 70 per m² = 70 × Curved surface area of the cone
= \(\frac{13728}{7}\) × 70
= \(₹\)137280
Thus, slant height of the tent is 26 m and the cost of the canvas is ₹ 137280.
In Fig. 9.26, A, B, C and D are four points on a circle. AC and BD intersect at a point E such that ∠ BEC = 130° and ∠ ECD = 20°. Find ∠ BAC.