Kathy, Tina and Min each sold an equal number of tarts. Kathy collected a total of $54.90 from selling 9 strawberry tarts and some cherry tarts. Tina collected a total of $56.70 from selling 11 strawberry tarts and some cherry tarts. How much did Min collect if she sold only cherry tarts?
Tina collected more money than Kathy from the sale of the tarts but the number of tarts sold by each girl was the same. This shows that each strawberry muffin is higher priced than each cherry muffin. 

Amount that Tina collected more than Kathy
= 56.70 - 54.90
= $1.80

Number of more strawberry tarts that Tina sold
= 11 - 9
= 2

Extra amount collected from the sale of each strawberry muffin
= 1.80 ÷ 2
= $0.90

Total extra amount collected from the sale of 9 strawberry tarts
= 9 x 0.90
= $8.10

If Kathy sold only cherry tarts, she would collect $8.10 less than her original amount.

Amount that Min collected if she sold only cherry tarts
= 54.90 - 8.10
= $46.80

Answer(s): $46.80