what is the height of a lamp whose two radii are 20cm and 30cm and slant height is 40cm respectively?
The height of the lamp can be found using the Pythagorean theorem. Let's call the height "h". Then we have:
h^2 = (slant height)^2 - (radius)^2
h^2 = 40^2 - 30^2
h^2 = 1600 - 900
h^2 = 700
h ≈ 26.46 cm
Therefore, the height of the lamp is approximately 26.46 cm.