SOLUTION
From the question, we are told that y varies inversely as x
This is mathematically written as
Now, we will remove the proportionality sign and replace it with equal to sign =
If we do this, we will intoduce a constant k
So we have the formula
We will substitute the values of x for 10 and y for 8 into the formula to get k, we have
Now, we will substitute k for 80 back into the formula to get the inverse function, we have
Hence the answer is option C