How Much Energy and Money Does Switching to a Compact Fluorescent Lamp Save?

[mz19]

A.) A 20-W compact fluorescent lamp replaces a 100-W incandescent bulb. How much energy does it save over its 10,000 hour lifetime?
B.) At $0.10 per kilowatt-hour, how much money does this save?

My attempt at answering:

Difference is wattage is 80-W, multiplied by 10,000 hours is 800,000 (not sure of the label here, is it Kilowatt hours?) saved.

Is part B just multiplying the 800,000 (UNIT) saved times (0.10) to get $80,000 saved?


Thank you for your help!

 

[256bits]

UNIT: simple
80 watt times 10,000 hours = 80 times 10,000 x watt times hours = 80,000 watt-hours.

B:
How many kw-hours is 80, 000 watt-hours?

 

[mz19]

80000 watt hours is 80kwh. So multiply 80 kWh to get $8.00?

 

[adjacent]

80000 watt hours is 80kwh. So multiply 80 kWh to get $8.00?

Ofcourse. 80 x 0.1 = 8

Or you can do this:
0.1$ --> 1Kwh
x --> 80

Just cross multiply, .

 

[xAxis]

UNIT: simple
80 watt times 10,000 hours = 80 times 10,000 x watt times hours = 80,000 watt-hours.

B:
How many kw-hours is 80, 000 watt-hours?

80x10000=800,000.
So you save 80 bucks