Question

The average of 5 numbers is 20 and 4 of the numbers are 10,15,20 and 25. If the numbers are arranged in ascending order,then the average of the last three is

Answer 1

Let the 5th no be X

Then ,

A.V=sum of total no./total no

=) 20 =5+10+ 15+20 +25 +X/5

=) 20 =75+X/5

=) 20×5=75+X

=) X=25

NOW,

5th no. =25

A.V OF LAST THREE NO. =)25+25+20/3

=)70/3

=)23.3