2.solve the following proportion. r/5=9/21 a. r=9 b. r=2.14 c. r=11.66 d. r=37.8 3.a recipe calls for 4 cups of sugar to make 4 dozen cookies. use the proportion to calculate how much sugar is needed to make 8 dozen cookies.

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.