We know that
l² = r² + h²
l² = (10.5)² + (36)²
l² = 110.25 + 1296
l² = 1406.5
l = √(1406.5)
l = 37.5 cm
Now,
CSA of cone = πrl
=> 22/7 × 10.5 × 37.5
=> 22 × 1.5 × 37.5
=> 1237.5 cm²
Area of 20 caps = 20 × 1237.5
=> 24750 cm²
I believe it is the last that is highlighted in yellow
Where’s the shapes and stuff ?
The hypotenuse should not be counted while finding the area of a triangle. The formula for the area of a triangle is 0.5bh. The Pythagorean theorem is a^2+b^2=c^2. The legs represent a and b, while the hypotenuse represents c.
