Body: Winter is almost here and most animals are migrating to warmer countries. 86 bird families flew away for the winter from near a mountain. If there were 45 bird families living near the mountain initially
Question: How many more bird families flew away for the winter than those that stayed behind?
question_concat: Winter is almost here and most animals are migrating to warmer countries. 86 bird families flew away for the winter from near a mountain. If there were 45 bird families living near the mountain initially How many more bird families flew away for the winter than those that stayed behind?