Zach agreed to shovel three of his neighbor's driveways for $7.50 per driveway. If he does this work every day for 7 days, how much more money will he need to earn a total of $300 to buy a new bike?

The more money needed to purchase a bike = $ 142.5

Step-by-step explanation:

Money earned for each driveway = $ 7.5

Money earned in three driveways = 7.5 * 3 = $ 22.5

Money earned in 7 days = 22.5 * 7 = $ 157.5

The price of new bike = $ 300

More money needed to purchase a bike = $ 300 - $ 157.5

More money needed to purchase a bike = $ 142.5

Therefore the more money needed to purchase a bike = $ 142.5