Найдите сумму 5 7/8+6 3/10 6 3/8+2 5/9 1 8/21+4 3/14+2 2/7

а) 5 7/8 + 6 3/10 = 47/8 + 63/10 = (235 + 252)/40 = 487/40 = 12 7/40.    5 7/8 = (5 * 8 + 7)/8 = 47/8.    6 3/10 = (6 * 10 + 3)/10 = 63/10.б) 6 3/8 + 2 5/9 = 51/8 + 23/9 = (459 + 184)/72 = 643/72 = 8 67/72.    6 3/8 = (6 * 8 + 3)/8 = 51/8.    2 5/9 = (2 * 9 + 5)/9 = 23/9.в) 1 8/21 + 4 3/14 + 2 2/7 = (58 + 177 + 96)/42 = 331/42 = 7 37/42.    1 8/21 = (1 * 21 + 8)/21 = 29/21.    4 3/14 = (4 * 14 + 3)/14 = 59/14.    2 2/7 = (2 * 7 + 2)/7 = 16/7. Ответ