.
The utility company charges 14 cents per kwh. What is the daily cost of keeping (a) an 8 watt lightbulb on for 8 hours?
(b) If a regular lightbulb is 60 watts, how much will you save for 30 days if you use it for 8 hours a day?
~~~~~~~~~~~~~~
These simple calculations are presented in the post by @CubeyThePenguin in some absurdist manner,
so I even can not read it and can not dispose them in the order in my mind.
THEREFORE, I redone the calculations in more organized way. See below.
(a) Consumed energy daily = 8 watt * 8 hours = 64 wt*h = 0.064 kwh.
Daily cost = 14 cents * 0.064 kwh = 0.896 cents.
Monthly cost = 0.896 cents * 30 days = 26.88 cents = 27 cents (rounded)
(b) Consumed energy (monthly) = 60 watt * 8 hours * 30 days = 14400 wt*h = 14.4 kwh.
Monthly cost = 14 cents * 14.4 kwh = 26.88 cents = 201.6 cents = 202 cents (rounded).
You save 202 cents - 27 cents = 175 cents = $1.75 monthly.
Solved // (correctly)