Contact us
Choose a category below so we can get back to you as quickly as possible.
圓的面積為s=πr2,半徑擴大2倍後面積為s=π(2r)2=π×4r2=4πr2,4πr2÷πr2=4,即圓的面積擴大4倍;10×4=40(平方釐米),答:這個圓的面積變為40平方釐米.故答案為:40.
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.