the daily wages of 80 workers of a factory:-

DAILY WAGES ($): 500-600,600-700,700-800,800-900,900-1000
12,,,,,,,,,,,,17,,,,,,,,,,,,,,28,,,,,,,,,,,,,14,,,,,,,,,,,,,,9
NO.OF WORKERS




find the mean of daily wages of the workers of the factory by using an appropriate method [step diviation method]​