Question

The average age of 120 employees in a company is 40 years. New employees with an average age of 32 joined the company over a period of 4
years. This resulted in the new average employee age to be 36. How many new employees joined in the 4 years?
110​

Answer 1

Answer:

120

Step-by-step explanation:

Average is given by:

sum of all occurrences/total no. of occurrences

using this:

Let the sum of the ages of the initial 120 employees be x.

Let the number of new employees added be y.

Let the sum of ages of the new employees be z.

Hence,

x/120 = 40

=> x = 40 x 120 = 4800

Hence, the sum of the ages of the initial 120 employees is 4800.

Hence,

z/y = 32

=> z = 32 x y

adding x and z to get the sum of ages of all the employees,

(120 + y employees)

(x + z)/(120 + y) = 36

=> {4800 + (32 x y)}/(120 + y) = 36

=>  4800 + 32y = 4320 + 36y

=> 4y = 480

=> y = 120

y is what we needed to find.

Hence, the number of new employees added is 120.