Find the average number of female employees in Marketing, HR and Production departments together.

Total number of male employees in the company = 640 Let the number of male employees in HR department be x. Now, number of male employees in IT department = x – 10 Number of male employees in Marketing department = x – 20 Number of male employees in Production department = x – 30 According to question, => x + x – 10 + x – 20 + x – 30 = 640 => 4x = 640 + 60 => x = 175 So the number of male employees in HR department = 175 Number of male employees in IT department = 165 Number of male employees in Marketing department = 155 Number of male employees in Production department = 145 Number of female employees in Marketing department = 145 Number of female employees in IT department = 160 Number of female employees in HR department = 160 × (7/8) = 140 Number of female employees in Production department = 160 × (5/8) = 100 Required average = (120 + 150 + 120)/3 = 390/3 = 130