Question

The height of the cone is decreased by curved surface area of cone by 20% and curved surface area of cone is increased of 50% of total surface area of cone . find the ratio between total surface area and curved surface area of cone

Answer 1

Let the change in volume be X

Change in volume× Volume of cone without change = Volume of Cone after change

$\begin{gathered}= X×\frac{3}{1} ×π×r2×h \\ \\ =\frac{3}{1}×π×(0.5r)2×1.2h \\ \\ = X=0.3\end{gathered}$

Which means 70% decrease

Answer 2

Answer:

$\huge\underbrace\mathcal\blue{Answer}$

Let the change in volume be X

Change in volume× Volume of cone without change = Volume of Cone after change

$x \times \frac{ 3}{1} \times \pi \times r {}^{2} \times h$

$= \frac{3}{1} \times \pi \times (0.5r) \times 1.2h$

$x = 0.3$

Hence , it will decrease 70% .