Let us consider the ratio to be x
So, as per the question's statement, we can write it as;


We will divide 9 on both the sides, we get;

So, for getting the number of puppy sold we have to multiply it with 5, we get:

They have sold 20 puppies.
Hence, the answer is
puppies.
How do you calculate a ratio?
Divide data A by data B to find your ratio. In the example above, 5/10 = 0.5. Multiply by 100 if you want a percentage. If you want your ratio as a percentage, multiply the answer by 100.
How to simplify a ratio?
Ratios can be fully simplified just like fractions. To simplify a ratio, divide all of the numbers in the ratio by the same number until they cannot be divided any more.