Answer:
3.35
Step-by-step explanation:
Take the total cost and subtract off the cost of the tax
We need to determine the tax
71.02 = original cost + original cos* tax rate
71.02 = original cost + original cost* .06
71.02 = original cost (1+ .06)
71.02 = original cost (1.06)
Divide each side by 1.06
71.06/1.06 = original cost before tax
67 = original cost before tax
Now to find the cost of each light bulb
Divide by the number of light bulbs
67/20=3.35
