B1. The trader received a shipment from the factory, which contained 480 more jars of mayonnaise than jars of mustard. After selling $80 \%$ of the jars of mayonnaise and a quarter of the jars of mustard, he found that he had 300 more jars of mustard than mayonnaise. How many jars of mustard and how many jars of mayonnaise were in the shipment he received from the factory?
B1.

![](https://cdn.mathpix.com/cropped/2024_06_07_70800c8f4239f8164bacg-18.jpg?height=60&width=1742&top_left_y=2123&top_left_x=171)

Determination that the trader has 20% of the jars of mustard left (or 1/5) ...................................................................

Determination that the trader has 75% of the jars of mayonnaise left (or 3/4) .................................................................

![](https://cdn.mathpix.com/cropped/2024_06_07_70800c8f4239f8164bacg-18.jpg?height=48&width=1739&top_left_y=2283&top_left_x=176)

Solving the system of equations ........................................................................................................................

Calculating the value of the first unknown \( G = 720 \) .......................................................................................

![](https://cdn.mathpix.com/cropped/2024_06_07_70800c8f4239f8164bacg-18.jpg?height=54&width=1736&top_left_y=2429&top_left_x=177)

Answer .......................................................................................................................