Friday

January 30, 2015

January 30, 2015

Posted by **Jen** on Tuesday, February 2, 2010 at 11:33am.

Thank You!

- Math -
**drwls**, Tuesday, February 2, 2010 at 11:55amBulb A total cost (including depreciation) = 18.07 t/10,000 + 0.008 t

= 0.02607 per hour

Bulb B total cost (including depreciation) = 0.39 t/1000 + .034 t

= 0.03439 per hour

A is always less expensive, in the long run, when bulb replacement costs are included. But they probably want you to know "How soon before you save enough to pay for the energy-saving bulb?". For that answer, solve this equation:

18.07 + 0.008 t = 0.39 + .034 t

17.68 = 0.026 t

t = 680 hours, before the lamp B burns out

Nowadays, compact fluorescent energy-saving bulbs cost quite a bit less than 18.07, and the savings come much sooner.

- Math -
**Jen**, Tuesday, February 2, 2010 at 12:01pmThank you very much! Great answer!

**Answer this Question**

**Related Questions**

Math- Best Buy - In comparing prices of canned peaches, Darren finds that a 10-...

maths - A box of 12 table costs 21 cents.The same brand is packaged in bottles ...

Physics - At 7.65 cents per kilowatt-hour, what does it cost to operate a 10.0 ...

math !!!! :O - Emily’s dad pays her for picking strawberries. Each hour she ...

economics - i have some questions please help Transportation equipment that was ...

Chemistry - Assume electricity cost 15 cents kw per hour....using the energy ...

Physics - A 60 W light bulb at 120 V is left on in your house to prevent ...

2nd grade Math - Wich 3 flowers add up to 85 cents? Tulip-48 cents Rose-52 cents...

Maths - Mrs Smith pays kate for babysitting by giving her 10 cents for the first...

Physical Science - A 60 W light bulb at 120 V is left on in your house to ...