######### yer numbers dont make sens
num numbers=25
AVERAEJ =36
sum=averaej*(num numbers)=25*36=900
yu sae first 13 numbers averaej=32,so sum av first 13=13*32=416
last 13=39, so sum=13*39= 507
sum av 2 grueps=416+507=923
##### last 13 duplikate the middel number...its in both grueps
middel numb=923=900=23
so middel number=900 -(