Final answer:
To find the minimum number of boxes Jan sold, we can set up an equation using the given information and solve for x. The solution to the equation will give us the minimum value of x, which represents the number of boxes Jan sold. In this case, the minimum number of boxes Jan sold is 12.
Step-by-step explanation:
Let's first assign a variable to represent the number of boxes Jan sold. We'll call this variable 'x'.
According to the problem, Leslie sold twice as many boxes as Jan, so the number of boxes Leslie sold is 2x.
Toni sold 7 more boxes than Jan, so the number of boxes Toni sold is x + 7.
The total number of boxes sold by the three girls is the sum of Jan's, Leslie's, and Toni's sales.
We can set up an equation to represent this: x + 2x + (x + 7) >= 55.
Simplifying the equation, we get 4x + 7 >= 55.
Subtracting 7 from both sides, we have 4x >= 48.
dividing both sides by 4, we find x >= 12.
Therefore, the minimum number of boxes Jan sold is 12.