Помогите математику 6 класс

2 7/9 * 15 = = 25/9 * 15/1 = 375/9 = 41 6/9 = 41 2/3 3 1/6 * 24 = 19/6 * 24/1 = 19/1 * 4/1 = 76 3 1/3 * 3/5 = 10/3 * 3/5 = 2 7 7/12 * 12/21 = 91/12 * 12/21 = 91/21 = 4 7/21 = 4 1/3 28 * 2 3/4 = 28 * 11/4 = 7 * 11 = 77 121 * 4 1/11 = 121/1 * 45/11 = 11 * 45 = 495 1 3/5 * 2 1/2 = 8/5 * 5/2 = 8/2 = 4 10 1/4 * 1 1/41 = 41/4 * 42/41 = 1/2 * 21/1 = 21/2 = 10,5