The average salary/head of all the workers in a workshop is Rs.700, if the average salary/head of 5 technician is Rs.800 and the average salary/head of the rest is Rs.650, the total no. of workers in the work-shop is ?
Choose the correct choice from the following:
A) 18  B) 19  C) 17  D) 16  E) 15

Rationale: let the total number of workers be y . so sum of salary for all workers = sum of salary of 5 technician + sum of salary for other y - 5 workers . 5 x 800 + 650 ( y - 5 ) = 700 y ⇒ 4000 + 650 y - 3250 = 700 y ⇒ 50 y = 750 ∴ y = 15 so total number of workers = 15 e
Answer: E