Jim pays $75 per month for a call phone plane plus $0.30 per minute beyond the first 1000 minutes. His bill was $105.60 last month. How many minutes did he use

Respuesta :

Answer: 1102 minutes

Explanation: Let x be the number of minutes Jim used 105.60 = 75 + 0.30 ( x − 1000 ) ⇒ 105.60 = 75 + 0.30 x − 300 ⇒ 105.60 = 0.30 x − 225

75 + 0.30x = 105.60

0.3x = 30.6

x = 102

1000 + 102 = 1102

Jim used 1102 minutes.