Question

A circular cake tin has radius 20 cm and height 7 cm. When cake mix was added to the tin, its
depth was 2 cm. After the cake was cooked it rose to 1.5 cm below the top of the tin.
a Sketch these two situations.
b Find the volume of: i the cake mix ii the cooked cake.
c What was the percentage increase in the volume of the cake while it cooked?​

Answer 1

Step-by-step explanation:

b (i) volume of the cake mix =

$\pi {r}^{2} h = 3.14 \times 20 \times 20 \times 2 = 2512 \: {cm}^{3}$

b (ii) height of cooked cake = 7- 1.5 = 5.5

volume = 3.14×20×20×5.5

= 6908 cm^3

c percentage increase in volume =

$100\times \frac{(volume \: of \: cooked \: cake \: - volume \: of \: cake \: mix)}{volume \: of \: cake \: mix}$

$100 \times \frac{(6908 - 2512)}{2512} = 175\%$