Why does the prove statement appear at the beginning of the proof?

Enter the missing numbers in the boxes to complete the table of equivalent ratios of lengths to widths. ? 18 8 ? 10 30 12 ?

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5