average age of 20 men is 50yr.5 new men,whose average age is 40yr,join them.find average age of all men?
If the average of the original 20 men is 50 years, what is the total sum of their ages?
What is the total sum of the new 5 men ?
Find the total sum of the ages of the 25 men, which will lead you to the average age of all of them.