Question

find the mean lifetime of tubes
lifetime. no of tubes
less than 300
400. 0
500. 20
600. 60
700. 116
800. 194
900. 265
1000. 324
1100. 374
1200. 392
490
​

Answer 1

Answer:

A frequency distribution of the of life times 400 T.V. picture tubes tested in a tube company is given below. Find the average life of tube.