Answer:
a. Her monthly average would have decreased by $19.57.
Step-by-step explanation:
To find out how not working on November would affect the average of Katie's tips, we first need to find the average of her working June until October only.
Average = 133.45 + 235.31 +239.45 + 258.87 + 298.45/5
Average = 1165.53 / 5
Average = $233.10
Now let's find out what her average is with the month of November.
Average = Average = 133.45 + 235.31 +239.45 + 258.87 + 298.45 + 115.67/6
Average = 1281.2 / 6
Average = 213.53
So now we can compare both averages.
233.10 - 213.53 = $19.57
We know that her average will decrease because 213.53 < 233.10.
Her average will decrease by $19.57.