Arko is twice as old as Adeeb. Eight years ago, Arko was 6 years younger than three times Adeeb's age at that time. How old will Arko be in 5 years?
A salesman's commission is 5% on all sales up to Tk. 10,000 and 4% of all sales exceeding this amount. He remits Tk. 31,100 to the parent company after deducting his commission. His sales were worth: