please I need to know how to do it manually. thanks

Light emitting diode (LEDs) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $ 42 and lasts for 1000 hours. A 15-watt LED, which provides the same light, costs $3.25 and lasts for 12.000 hours. A kilowatt hour of electricity costs $.118. A kilowatt-hour is 1000 watts for 1 hour However, electricity costs actually vary quite a bit depending on location and user type. An industrial user in West Virginia might pay $.04 per kilowatt-hour whereas a residential user in Hawaii might pay $.25. You require a return of 11 percent and use a light fixture 500 hours per year. What is the break-even cost per kilowatt-hour? (Do not round intermediate calculations and round your answer to 6 decimal places, e.g., 32.161616.) X Answer is complete but not entirely correct. Break-even cost 8.904594 X Light emitting diode (LEDs) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $ 42 and lasts for 1000 hours. A 15-watt LED, which provides the same light, costs $3.25 and lasts for 12.000 hours. A kilowatt hour of electricity costs $.118. A kilowatt-hour is 1000 watts for 1 hour However, electricity costs actually vary quite a bit depending on location and user type. An industrial user in West Virginia might pay $.04 per kilowatt-hour whereas a residential user in Hawaii might pay $.25. You require a return of 11 percent and use a light fixture 500 hours per year. What is the break-even cost per kilowatt-hour? (Do not round intermediate calculations and round your answer to 6 decimal places, e.g., 32.161616.) X Answer is complete but not entirely correct. Break-even cost 8.904594 X