1 7/8 : 8 1/3 = х : 4/9
15/8 / 25/3 = x/ 4/9 15/8 * 3/25 = x / 4/9 9/40 =x / 4/9 x= 9/40 * 4/9 x= 1/10 проверяем: 15/8 * 3/25 = 1/10 / 4/9 9/40 = 1/10 *9/4 9/40 = 9/40