In a certain factory there are 10 officers, 60 clerks and 400 workers. Their average salaries are Rs. 627; Rs. 230 and Rs. 120 respectively. Find the average
salaries of all the employees of the factory together.

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.

step-by-step explanation: