the average salary / head of all the workers in a workshop is rs . 1000 , if the average salary / head of 10 technician is rs . 1200 and the average salary / head of the rest is rs . 820 , the total no . of workers in the work - shop is ?
let the total number of workers be y . so sum of salary for all workers = sum of salary of 10 technician + sum of salary for other y - 10 workers . 10 x 1200 + 820 ( y - 10 ) = 1000 y ⇒ 12000 + 820 y - 8200 = 1000 y ⇒ 180 y = 3800 ∴ y = 190 / 9 so total number of workers = 190 / 9 d
divide(subtract(multiply(10, 1200), multiply(820, 10)), subtract(1000, 820))