deleteCharAt() of StringBuilder

[Tarun Mohandas]

I am preparing for OCA from a study guide. In that there is a question:

StringBuilder sb=new StringBuilder;

Which of the following are valid uses of sb variable?

I answered it right but it is given in answers that the following is also a correct usage:

sb.deleteCharAt(34.5);

I checked docs.oracle and they have given StringBuilder deleteCharAt(int index)

Based on the above, the deleteCharAt syntax is not correct unless a cast is provided right? How can this be correct syntax?

[Jeff Verdegan]

If the guide says you can pass 34.5 to a method taking int, then the guide is wrong.

[Tarun Mohandas]

Thank you