Heather has $490 in her savings account. She withdraws $15 per week for gas. Enter an equation Heather can use to see how many weeks it will take for her to have a balance of $310.

Aresearch study is done to find the average age of all u.s. factory workers. the researchers asked every factory worker in ohio what their birth year is. this research is an example of a census survey convenience sample simple random sample