Joe stops at his neighborhood drive-through coffee shop for breakfast on the go each morning. He usually gets a coffee for $1.25 and a bagel for $1.75. He is trying to save up to buy a new chair for his living room, so he decides to brew coffee at home and eat grocery store bagels before he leaves for work. He buys coffee beans ($7.00 for a bag that lasts about 3 weeks) and bagels ($4.00 for a bag of 6 bagels). How much will he save over a whole year (based on 260 workdays per year)?

To calculate how much Joe will save over a whole year by making his breakfast at home instead of buying it at the coffee shop, we need to consider the costs of his previous routine versus his new routine.

Previous routine:

- Coffee cost per day: $1.25

- Bagel cost per day: $1.75

- Total cost per day: $1.25 + $1.75 = $3.00

New routine:

- Cost of coffee beans per day: $7.00 / 21 days = $7.00 / 3 = $2.33 per day

- Cost of bagel per day: $4.00 / 6 bagels = $4.00 / 6 = $0.67 per bagel

- Total cost per day: $2.33 + $0.67 = $3.00

Therefore, Joe's cost per day remains the same at $3.00 even after switching to making breakfast at home.

To find out how much Joe will save over a whole year:

- Total cost per day: $3.00

- Workdays per year: 260

Total savings over a year:

$3.00 * 260 = $780.00

Joe will save $780.00 over a whole year by making his breakfast at home instead of buying it at the coffee shop.