The production of electric bulbs in different factories is shown in the following table. Find the median of the production.

Answer

The median of the production is `52750` lamps.

Explanation

Here, total number of frequencies ` N = Sigma f_(i) = 105`
` :. N/2 = (105)/2= 52.5`
Cumulative frequency which is greater than `52.5` is 67.
` :. ` the corresponding class `50-60` is the median class.
` L = 50, f = 20, cf = 47, h = 10`.
Median ` = L + [(N/2 - cf)/f] xx h`
` = 50 + ((52.5 - 47)/20) xx 10`
` = 50 + (5.5)/2 = 50 +2.75 = 52.75` thousand
` = 52750`.