Final answer:
To find the percent error, calculate the absolute error and divide it by the actual value, then multiply by 100.
Step-by-step explanation:
To find the percent error, we first need to calculate the absolute error, which is the difference between the estimated value and the actual value.
In this case, the estimated value is a half-gallon, or 64 ounces, and the actual value is 72 ounces.
So, the absolute error is 72 - 64 = 8 ounces.
Next, we calculate the percent error by dividing the absolute error by the actual value and multiplying by 100. So, the percent error is (8 / 72) * 100 ≈ 11.1%.
Therefore, the percent error of Jin's mother's estimate is approximately 11.1%.