 
 <translate> Sum of all the 13 numbers = 13 * 59 = 767
Sum of the first 7 of them = 7 * 57 = 399
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 399 - 767 = 59.
Thus, the answer is (A). <hau> Jimlar dukkan lambobi 13 = 13 * 59 = 767 Jimlar na farko 7 daga cikinsu = 7 * 57 = 399 Jimlar 7 na ƙarshe daga cikinsu = 7 * 61 = 427 Saboda haka, lamba ta takwas = 427 + 399 - 767 = 59. Saboda haka, amsar ita ce (A). 