Question

What is the height of a circular cone? i. the area of that cone is equal to the area of a rectangle whose length is 33 cm. ii. the area of the base of that cone is 154 sq. cm?

Answer 1

Given info : The area of a cone is equal to the area of a rectangle whose length is 33cm and the area of the base of that come is 154 cm².

To find : the height of the cone is ...

solution : area of base of cone = 154 cm²

⇒πr² = 154 cm²

⇒r² = 154/(22/7) = 49

⇒r = 7 cm

area of cone = πrl

area of rectangle = L × B

∵ area of cone = area of rectangle

∴ πrl = L × B

⇒22/7 × 7 × l = 33 × B

⇒2l = 3B

⇒l = 3B/2 = 1.5B

so height of cone , h = √(l² - r²)

= √{(1.5B)² - 7²)

= √(2.25B² - 49) , you see without breath of rectangle we can't able to find out height of cone.

so, both I and II are not sufficient to find the answer.