Num BankPosition Shares BalanceStarting 100 £0.00Sell at 8p 0 £8.00Buy Back 20p 100 -£12.00Sell at 50p 0 £38.00OrSell at 70p 0 £58.00OrSell at 100p 0 £88.00OrSell at 120p 0 £108.00