Would You Rather...? > Uncategorized > Would You Rather… Would You Rather… stevens009November 3, 2014Uncategorized Buy a fancy 5-year eco-lightbulb for $9.79? Or pay 70 cents per lightbulb, but replace them every 5 months? h/t @mrvaudrey Whichever answer you choose, please justify your reasoning using mathematics. Share this WYR:TwitterFacebookGoogleEmailPocketPrintPinterest Post navigation ← Previous post Next post → Comments (2) MC November 5, 2014 at 7:55 pm And …. CFL bulb uses 24 watts, regular bulb uses 100W Cost of electricity is $0.13 per kilowatt-hour. watts/1000 = kilowatts. kilowatts * hours on = kilowatt-hours So 100 watt bulb left on for 12 hours per day would be 1.2 kWh which would cost $1.56 Reply ↓ hannah November 14, 2014 at 5:41 pm i would prefer regular bulbs over the eco bulb because its a dollar cheaper for each 5 years Reply ↓ Leave a Comment Cancel reply Your email address will not be published. Required fields are marked * Notify me of follow-up comments by email. Notify me of new posts by email.