Use a proportion to solve each problem.
St. Paul Island in Alaska has 12 fur seal rookeries (breeding places). In $1961,$ to estimate the fur seal pup population in the Gorbath rookery, 4963 fur seal pups were tagged in early August. In late August, a sample of 900 pups was observed and 218 of these were found to have been previously tagged. Estimate the total number of fur seal pups in this rookery.