Mushroom pizza

Jirka invited four friends to his home for a home cinema. They agreed to order something to eat. They had pizza delivered from a nearby pizzeria. They ordered ham pizza, cheese pizza, quattro formaggi, mushroom pizza, margherita, and hawaii. Each pizza they divided into 5 equal pieces.
1. What area did one piece have if the diameter of the pizza was 30 cm?
2. What large area did all the pieces of pizza for each of the boys form?

Final Answer:

S₁ =  141.3717 cm²
S₂ =  1060.2875 cm²

Step-by-step explanation:

$$\begin{gathered} D=30\text{cm} \\ r=D/2=30/2=15\text{cm} \\ {S}_1=\frac{1}{5}\cdot \pi \cdot r^2=\frac{1}{5}\cdot 3.1416\cdot 15^2=141.3717{\text{cm}}^2 \end{gathered}$$

$S_2=S_1\cdot \frac{6\cdot 5}{4}=141.3717\cdot \frac{6\cdot 5}{4}=1060.2875{\text{cm}}^2$

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