Answer :
He still has to collect 30 coins
(2,000-1951=49, but he needs the coin from 1951 as well so it is equivalent to 50)
50 x .4=20
50-20=30
(2,000-1951=49, but he needs the coin from 1951 as well so it is equivalent to 50)
50 x .4=20
50-20=30