Age Problem (Equation Writing Help) I am new to writing equations and have to write and solve the following:

Kevin is $7$ less than three times Maria's age.  If Kevin is $17$, how old is Maria?

I think Maria is $30$ if Kevin is $17$ because Kevin is $7$ less than $3$ times Maria's age but I don't know how to put it in the correct equation format.  Do I need more than one variable?  This is where my confusion is.

Thanks for any help or tips!

Edited to add - I think Maria is $30$ because if Kevin is $17$ and he is $7$ less than three times Maria's age $(17-7=10)$ and $10\times 3 =30$.
You only need one variable.

Let Maria's age be $x$. So $3x-7=17$ since Kevin is $17$. Solving, we get $x=8$. So Maria is $8$ years old.

In other words, $3x-7=17$ is the equation you want.

(If you try to have Maria being $30$, then Kevin's age would be $3\times30-7=83$!! Which I don't think is $17$. Wait, am I wrong?)
Kevin is $17$, so add $7$ to $17$, then divide by $3$.