Let the number of workers = x Average salary of all the workers x = Rs 850 Total salary of all the workers = Rs 850x Average salary of seven technicians = Rs 1,000 Total salary = 7 × 1,000 = Rs 7,000 Average salary of ( x - 7) workers = Rs 780 Total salary = (x - 7) 780 According to the statement, 850x=7,000+(x−7)780 850x=7,000+780x−5,460 850x−780=7,000−5,460 70x=1,540 x=22 workers