f the product $\frac{3}{2}\cdot\frac{4}{3}\cdot\frac{5}{4}\cdot\frac{6}{5}\cdot\ldots\cdot\frac{a}{b}=9$, what is the sum of $a$ and $b$?

We notice that all the numerators and denominators cancel each other out except for $a$ and $b$. This leaves us with $\frac{a}{b}=9$. Therefore, $a=9b$.

To find the sum of $a$ and $b$, we substitute $a=9b$ into the equation $a+b=10b$. Since we do not have enough information to determine the exact values of $a$ and $b$, the sum can be expressed as $10b$.

Therefore, the sum of $a$ and $b$ is $\boxed{10}$.

No, try again

We see that the product simplifies to $\frac{a}{2}$, where $a$ is the numerator corresponding to the fraction $\frac{a}{2}$. Since this product simplifies to 9, we have:

\[\frac{a}{2} = 9\]
\[a = 18\].

Therefore, the sum of $a$ and $b$ is $18+2=\boxed{20}$.