As shown in the figure, the shadow is 2 / 5 of the area of the big circle and 1 / 3 of the area of the small circle. What is the ratio of the area of the big circle to the area of the small circle
(1) Because the shadow is 2 / 5 of the area of the big circle and 1 / 3 of the area of the small circle, we can get the following equation:
Large circle area × 2 / 5 = 1 / 3 of small circle area Change the equation into the proportion formula and simplify the ratio
Large circle area: small circle area = 1 / 3:2 / 5 = 5:6