probability problem

Question

there is a 20% chance the total employees will increase by 300, 70% chance will increase by 400 employees and 10% chance will derease by 500 employees, determine the expected gain or loss of employees

Answer 1

x P(x)

300 0.2

400 0.7

-500 0.1

expected increase/decrease = 0.2 * 300 + 0.7 * 400 - 0.1 * 500 = 150 + 280 - 50 = 380 (increase)