Mary will bake 15 trays.
Firstly converting the amount of flour into grams that Mary has.
As per the known facts 1 kilogram = 1000 grams.
So, amount of flour in grams = 3 × 1000
Performing multiplication to calculate amount of flour
Amount of flour in grams = 3000 grams.
Now, 200 grams flour is required by number of trays = 1
So, 3000 grams flour will be required by number of trays = (1÷200)×3000
Performing multiplication and division to find the number of trays that can be baked
Number of trays = 15
Hence, Mary can bake 15 trays of muffins with 3 kilograms of flour.
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