Greta's bicycle is old and rusty. Her parents won't buy her a new one unless she does more chores around the house. Greta's dad said he will buy a new bicycle if Greta mows the lawn, rakes the leaves, and washes the windows every weekend for 16 weeks in a row. Greta is very motivated and does her chores for 3 weeks straight. Which equation can Greta use to find how many more weeks w she needs to do her chores before her parents will buy her a new bicycle?