the average age of a group of n people is 14 years old . one more person aged 34 joins the group and the new average is 16 years old . what is the value of n ?
"14 n + 34 = 16 ( n + 1 ) 2 n = 18 n = 9 the answer is c ."
divide(subtract(34, 16), subtract(16, 14))