How do you calculate the approximate mean monthly salary of 100 graduates

monthly salary number of graduate

1001-1400 1

1401-1800 11

1801-2200 14

2201-2600 38

2601 3000 36.

The mean monthly salary of these 100 graduates is $2388.5

Step-by-step explanation:

First, lets make all of the salaries a set, so:

S = {S1, S2, S3, S4, S5}

where

S1 = {1001-1400}

S2 = {1401-1800}

S3 = {1801-2200}

S4 = {2201-2600}

S5 = {2601-3000}

Each element S1, S2, ..., S5 will have it's own mean, that will be the upper range + lower range divided by 2.

So

M (S1) = (1400+1001) / 2 = 2401/2 = 1200.5

M (S2) = (1401+1800) / 2 = 3201/2 = 1600.5

M (S3) = (1801+2200) / 2 = 4001/2 = 2000.5

M (S4) = (2201+2600) / 2 = 4801/2 = 2400.5

M (S5) = (2601+3000) / 2 = 5601/2 = 2800.5

To find the approximate mean, now we calculate a weigthed mean between M (S1), M (S2), ..., M (S5)

So the mean will be

M = (M (S1) + 11*M (S2) + 14*M (S3) + 38*M (S4) + 36*M (S5)) / 100

M = 238850/100

M = 2388.5

So the mean monthly salary of these 100 graduates is $2388.5