5. Some chocolates were bought at Tk. 8 per piece, and sold them at Tk. 8.50 per piece and then the profit was Tk. 25. How many chocolates were bought?​

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.