2. At a certain firm 81 per cent of the investments will mature in more than 1 year and 27 per cent of the investments will mature in more than 2 years. What per cent of the investments of the firm will mature in more than 1 year but nor in not more than 2 years?
9. The average of a list of positive numbers is 20 per cent of the sum of the numbers. How many numbers are there in the list?