Twenty- four divided by the difference between 1 1/2 and 3/4

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

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If there are 12 moths and some have 31 days and others have 30 days how many have 28 days?