One half of the employs of Al Karim Co. earn salaries sabove Rs.18,000 monthly. One third of the reminder earn salaries between Rs.15,000 and Rs.18,000. What part of the staff earns below Rs.15,000?
A word processing operator typed 44 words per minute. After practice, the operator's speed increased to 55 words per minutes. By what percent did the operator's speed increase?