Question

Two years ago the mean age of 40 people was 11 years. Now a person left the group
and the mean age has changed to 12 years. Find the age of the person who left the group.​

Answer 1

Answer:

52 years

Step-by-step explanation:

Two years ago the mean age for 40 people was 11 years.

= Total age of 40 people two years ago =40×11=440

Now, after two years the total age should go up =(2×40)+440=80+440=520.

= When one person left, the for 39 people the mean age is 12.

=Total age of 39 people =39×12=468

= Required age =520−468=52years