age riddle

Fauja singh ,the grand father of shamsher singh had captured four spies of hitler's nazy arm. it was after some year that he was rewarded for this act of bravery with Rs. 5000in cash and a special medal.
At the time of the receipt of the reward, fauja singh's age plus the age of his son jarnail singh,
was half the age of shamsher singh plus the age of fauja singh, as would be on 30 march1972.

Ten years thereafter, i.e. in the year 1982,shamsher singh's age was 1/4 of his grand fathers's age, while his father jarnail singh's age was 8years less than three times of shamsher singh's age.
 can you tell what was the ages of all the three in 1983?.