Joe leaves $3 as a tip for a meal that cost $22. If a good tip is between 15% and @0% is this a good tip?

Yes, a good tip would either be $3 or $4. To calculate the tip, you just take the overall total and multiply it by the percentage in decimal form.

Total = $22

15% =.15

20% =.20

(22) x (.15) = 3.3 = $3

(22) x (.20) = 4.4 = $4