the average age of 40 passengers in a ferry is 35 . what is the average age of the new group formed when combining the passengers with the 5 crew members of ferry whose average age is 25 ?
sum of ages of passengers = 40 x 35 = 1400 sum of ages of crew = 25 x 5 = 125 sum of ages of new group formed = 1525 average = 1525 / 45 = 38.89 answer : b
divide(add(multiply(35, 40), multiply(5, 25)), add(35, 5))