Alex is saving money because she would like to purchase the new video gaming system that everyone has been talking about. After two weeks of saving, she had $47. After 24 weeks of saving, she had $430. Approximately how many dollars per week did Alex save on average between weeks 2 and 24? (2 points)
$15.96 per week
$17.41 per week
$17.91 per week
$19.88 per week