Editing Openai/694f3cf5-8aa0-8005-b99d-6d3d0de02934 (section)

===== 外側のおうぎ形 − 内側のおうぎ形 =====

S=π×62×120360−π×42×120360S
= \pi \times 6^2 \times \frac{120}{360}
* \pi \times 4^2 \times \frac{120}{360}S=π×62×360120−π×42×360120
=π(36−16)×13=π×20×13= \pi (36 - 16) \times \frac{1}{3}
= \pi \times 20 \times \frac{1}{3}=π(36−16)×31=π×20×31
20π3 cm2\boxed{\frac{20\pi}{3}\ \text{cm}^2}320π cm2
👉 答え：20π3 cm2\displaystyle \frac{20\pi}{3}\ \text{cm}^2320π cm2