One out of every 500 light bulbs are defected.

One out of every 500 light bulbs are defected. If 5 out of every 10 defected light bulbs have a broken glass and there are 20 broken glass light bulbs in the shipment, how many light bulbs total are there in the shipment?

Quiz

Answer/Solution

20,000

Steps/Work

out of 500 only 1 bulb is defective.So for 10 defective bulbs, we must have 5000 bulbs
Now out of these 10 bulbs, 5 bulbs, have broken glass
i.e 5 broken glass out of 5000 bulbs
20 broken glass will be from 20000 bulbs
Answer is D