One out of every 500 light bulbs are defected. If 4 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?  Select the correct option:
A) 2,000 B) 5,000 C) 10,000 D) 25,000 E) 52,000
out of 500 only 1 bulb is defective.So for 10 defective bulbs, we must have 5000 bulbs   Now out of these 10 bulbs, 4 bulbs, have broken glass   i.e 4 broken glass out of 5000 bulbs   20 broken glass will be from 25000 bulbs   Answer is 25,000
<result>D</result>
One out of every 500 light bulbs are defected. If 4 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?