I need to find the number that's missing

Asap (explain how you got it as well for brainliest)i tried 1: 2 and 2: 3 and they were wrong.picture of figure: in the figure below, the segment is parallel to one side of the triangle. the ratio of 12 to y is1: 21: 31: 42: 3

Pete is making decorations for a dinner party. the instructions tell him to use 9 flowers for a medium-sized decoration. complete each statement to adjust the flowers for different-sized decorations based on these instructions.

You are designing a rectangular pet pen for your new baby puppy. you have 30 feet of fencing you would like the fencing to be 6 1/3 feet longer than the width