Correct Response: B. Let g = the number of G phones, and z = the number of Z phones. The total number of phones is 400, so g + z = 400. Each G phone has a retail value of $65, and each Z phone has a retail value of $15, so the value of the G phones is 65(number of G phones) = 65g, and by the same reasoning the value of the Z phones is 15z. The total value of the two phones is $11,700, so the following equation is true: 65g + 15z = 11,700. Solving two equations for g gives g = 114. Response A is 114/2 = 57, which is the number of G phones divided by two. Response C results from adding the total value of phones and the total number of phones, and then dividing by the higher-priced phone: 11,700 + 400 = 12,100 and 12,100/65 = 187. Response D results from dividing the total value of phones by the difference in price between the two phones: 11,700/(65 – 15) = 11,700/50 = 234.
