Welcome to Westonci.ca, the place where your questions find answers from a community of knowledgeable experts. Get quick and reliable solutions to your questions from a community of experienced professionals on our platform. Get detailed and accurate answers to your questions from a dedicated community of experts on our Q&A platform.

During one month, a homeowner used 300 units of electricity and 120 units of gas for a total cost of $114.00. The next month, 290 units of electricity and 150 units of gas were used for a total cost of $115.30. Find the cost per unit of gas.
$_____

Sagot :

Answer:

  • $0.15

Step-by-step explanation:

  • Cost of electricity = x
  • Cost of gas = y

Based on the given, we have equations:

  • 300x + 120y = 114
  • 290x + 150y = 115.30

Multiply the first equation by 29 and the second one by 30, then subtract the first equation from the second:

  • 30*(290x) -  29(300x) + 30(150y) - 29(120y) =30(115.3) -  29(114)
  • 4500y - 3480y = 153
  • 1020y = 153
  • y = 153/1020
  • y = 0.15

The cost per unit of gas is $0.15