Solution:Let- weight of new comer is y and Average weight of 8 men is x.Total weight of 8 person = 8x After joining new person total weight =
8x-65+y
New Average = old Average + 1.5.
(8x - 65 + y)/8 = x + 1.5
8x - 65 + y = 8x + 12.0
y = 65 + 12
y = 77kg