Final answer:
The sample ratio of defective light bulbs to total light bulbs in the shipment is calculated by dividing the number of defective light bulbs by the total in the sample and multiplying by 100% to get 4%.
Step-by-step explanation:
To find the sample ratio of defective light bulbs to total light bulbs in the shipment written as a percent, we first observe that in our sample of 75 light bulbs, there are 3 that are defective. To find this ratio as a percent, we perform the following calculation:
Ratio = (Number of Defective Light Bulbs / Total Number of Light Bulbs) × 100%
Ratio = (3 / 75) × 100% = 0.04 × 100% = 4%
Therefore, the sample ratio of defective light bulbs to total light bulbs is 4%, which corresponds to option A.