A microwave can reheat 1 cup of coffee in 30 seconds. It takes a coffee maker 10 minutes to brew 12 cups of coffee. If the coffee maker requires 900 watts of power and the microwave requires 1200 watts of power, does it require more
energy to brew 12 cups with the coffee maker or reheat 12 cups of coffee in a microwave?
The coffee maker requires more energy.
The microwave requires more energy.
They require the same amount of energy.
The answer cannot be determined without more information.

The coffee-maker requires more energy.

Explanation:

Explanation: At 30 seconds a cup, the microwave will require 6 minutes to reheat the 12 cups of coffee. This is 1/10 of an hour, so the microwave uses 1200/10 = 120 watt-hours of energy. The coffee-maker requires 10 minutes to brew 12 cups of coffee, or 1/6 of an hour. This means it will use 900/6 = 150 watt-hours of energy.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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