Employment Rate Comparison of Graduates

In a recent study, the average employment rate of college graduates within the first year of graduation was observed to vary based on their field of study. The study provided the following average employment rates (in percentages) for three different fields of study:

1. Engineering: 90%
2. Humanities: 60%
3. Business: 80%

Furthermore, the study also stated that graduates from the Engineering field were employed at a rate significantly higher than the overall average of all graduates, while graduates from Humanities had the lowest employment rate among the three fields.

Based on this data, compare the following two quantities:

Quantity A: The average employment rate of Engineering graduates.
Quantity B: The average employment rate of all graduates.

Assume that the number of graduates in each field is equal.