Final answer:
The percentage increase in the waiter's tips from Friday to Saturday is calculated by dividing the increase in tips by the original amount and then multiplying by 100, resulting in a 21.67% increase.
Step-by-step explanation:
The waiter earned $300 on Friday and $365 on Saturday. To find the percentage increase in the tips from Friday to Saturday, we calculate the increase in amount first and then divide it by the original amount from Friday. The formula to calculate percentage increase is as follows:
Percentage Increase = (Increase in Amount / Original Amount) x 100
We first subtract the Friday earnings from the Saturday earnings to find the increase:
Increase in Amount = Saturday Tips - Friday Tips
= $365 - $300
= $65
Now, we divide this increase by the original amount (Friday's earnings) and multiply by 100 to find the percentage:
Percentage Increase = ($65 / $300) x 100
= 0.2167 x 100
= 21.67%
Therefore, the percentage increase in tips from Friday to Saturday is 21.67%, which corresponds to option B.