Id. k why but yes and this makes me go yes

Hi, can anyone show me how to do this problem? 100 points for this. in advance

Out of $20$ creepy-crawly creatures in a room, $80\%$ are flies and $20\%$ are spiders. if $s\%$ of the total legs belong to spiders, what is $s$?

Each day jake donates money to the global.