SOLUTION: The cost of the electricity to play a radio varies directly with the number of hours it is playing. It costs $10.00 to play a radio continuously for 20 days. At this rate, what wo
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Question 717322: The cost of the electricity to play a radio varies directly with the number of hours it is playing. It costs $10.00 to play a radio continuously for 20 days. At this rate, what would it cost to operate the radio for one day? Answer by jndarrell(58) (Show Source):
You can put this solution on YOUR website! When you see word problems like this...you should be thinking of proportions. Always remember that the numerator and denominator should be the same unit placement on both sides.
For this equation, you can place $$ over days. Place x in the space for which you are solving or not provided a value for.
10.00 over 20 is equal to x over 1
10.00/20 = x/1
CROSS MULTIPLY
20x=10.00
Divide both sides by 20 to get the x alone
x=0.5
Don't forget when reporting your solution to include the units, $0.50
To check your work, plug the answer you got for x back into your original equation.
:)
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