If two values and are inversely proportional, their product is <em>always</em> some maintained constant (the product of and is always maintained). This way, if one goes up, the other must go down by the same extent. By definition, this represents an inversely proportional relationship.
Therefore, we can simply find this constant by multiplying the given values of and :
The constant must be maintained as the product of and for all values of and for them to be inversely proportional. Thus, we have the equation:
From the information given, you can use a rule of three to calculate the constant rate that Kendra swims per day given that she swims 126 miles in 3 days:
3 days → 126 miles
1 day → x
x=(1*126)/3=42 miles
According to this, the answer is that Kendra swims 42 miles per day.