Question
The average age of a group of
five friends is 78 years. If a friend, aged 48 years, is replaced by another friend, then the average age of each friend in the group will increase by 4 years. Find the age of the friend who was replaced.Solution
ATQ,
Sum of the ages of 5 friends, initially = 5 X 78 = 390 years Let the age of the new friend who joined the group = 'y' years Therefore, 390 - 48 + y = 5 X (78 + 4) Or, 'y' = 410 - 342 = 68 Therefore, age of the new friend = 68 years Alternate Solution Age of the new friend = age of the friend replaced + increase in average age X number of friends So, age of the new friend = 48 + 5 X 4 = 48 + 20 = 68 years
Six items, T, U, V, W, X and Y are placed one above another. Two items are placed above X. V is placed just above Y. Three items are placed between Y an...
How many students appear for RBI exam?
Which of the following is Correct?
The number of persons living between S and the one whose experience is 7 years is the same p?
On which floor does the person live who likes Nokia?
Who among the following has born on 17th of August?
Who among the following lives on Floor-2?
What is the difference between the floor number of O and N?
Johnny went to which of the following Islands?
What is Megha by profession?
Relevant for Exams:
