2/3 из 3 3/4= 7/18 из 4 1/2= 8/13 из 4 1/16=
3 3/4 * 2/3 = 15/4 * 2/3 = 5/2 = 2 1/2 4 1/2 * 7/18 = 9/2 * 7/18 = 7/4 = 1 3/4 4 1/16 * 8/13 = 65/16 * 8/13 = 5/2 = 2 1/2