Select the correct solution set. 50 ≥ 15x

{x | x ≤ 10/3}
{x | x ≥ 10/3}
{x | x > 10/3}

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.