 
<translate> Jimlar shekarun ƙungiyar da ke da mutane 4 da matsakaicin 40 = 4x40 = 160 Jimlar shekarun ƙungiyar da ke da mutane 5 da matsakaicin 38 = 5x38 = 190 Shekaru na sabon mutumin da aka kara wa kungiyar = 190-160 = 30 Amsar: (C). <eng> Sum of the ages of the group having 4 persons and average 40 = 4x40 = 160
Sum of the ages of the group having 5 persons and average 38 = 5x38 = 190
Age of the new person added to the group = 190-160 = 30 The answer: (C). 