An electronic firm finds that 4% of is defective.

out of every 100 only 96 are useful

96 can be delivered out of 100

5000 can be delivered out of (100x5000) / 96 = 5208.33

as whole number next to it is 5209

Now to verify

4% of 5209 = 4x5209/100 = 208.36 will be defective

or 209 rounded off

5209 - 209 = 5000 ready to be delivered

So answer is 5209

this is not asking a question and i am not sure what the question you are asking is.