Use the assumed-mean method to find the mean weekly wages from the data given below.
Weekly wages (in Rs) | 800 | 820 | 860 | 900 | 920 | 980 | 1000 |
No. of workers | 7 | 14 | 19 | 25 | 20 | 10 | 5 |
Let assume mean be A = 900
Now we can arrange data in below format
Weekly wages (in Rs) (xi) | No. of workers (fi) | di = xi– A | fi × di |
800 | 7 | -100 | -700 |
820 | 14 | -80 | -1120 |
860 | 19 | -40 | -760 |
900 | 25 | 0 | 0 |
920 | 20 | 20 | 400 |
980 | 10 | 80 | 800 |
1000 | 5 | 100 | 500 |
∑fi = 100 | ∑(di×fi) = -880 |
We have,
Mean =
= 891.21
Hence the mean is 891.21