It will take 14 years for the beaches to erode by 21 feet.
Given,
beaches are eroding per year = 1.5 feet
After 21 years, the eroding will be -
= 21 / 1.5
= 14 years
So, the eroding will be 21 feet after 14 years.
Division is one of the four basic operations of arithmetic, which are the methods by which numbers are combined to form new numbers. Addition, subtraction, and multiplication are the other operations.
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