 
<translate> Na Tuesday, Billy riri mkpụrụ osisi apụl 2 * 2 = 4. N'ụbọchị Fraịde, o riri mkpụrụ osisi apụl abụọ na ọkara. N'ụbọchị Tọzdee, o riri mkpụrụ osisi apụl anọ. Ya mere, n'ụbọchị Monday, Tuesday, Thursday, na Friday, Billy riri mkpụrụ osisi apụl 2+4+4+1 = 11. Nke a pụtara na n'ụbọchị Wednesday, ọ ghaghị iriwo apụl 20 <unk> 11 = 9. Ya mere, azịza ya bụ 9. <eng> On Tuesday, Billy ate 2 * 2 = 4 apples. On Friday, he ate 2 * 0.5 = 1 apple. On Thursday, he ate 4 * 1 = 4 apples. So for Monday, Tuesday, Thursday, and Friday, Billy ate a total of 2 + 4 + 4 + 1 = 11 apples. This means that on Wednesday, he must have eaten 20 – 11 = 9 apples. So, the answer is 9. 