Can you help me with this Java question? (Quiz Tomorrow)

[MeltyMoon]

I'm taking a computer science class in my highschool and my teacher wasn't able to see me for extra help today. I have a quiz tomorrow with a question like this on it, can anyone help me study by solving this example question? I would greatly appreciate it . 

Here's the rundown of the question;

The client supplies a string that contains a mathematical sentence, using the various operators (so +,-,*,/) an example would be 3.4*5+6-6.7

The method should return a String value that is simplified and follows the rules of PEMDAS.

 

I understand how to use Double.parseDouble() would be used to convert the string to a double value, along with most of the indexOf variants,  however the syntax of the code required for this question confuses me. 

Can anyone help? You'd be doing a student a huge favor!

[nsyedhasan]

@MeltyMoon To do so you have to use  Y=d.parseDouble(X). This website has an example. http://www.tutorialspoint.com/java/lang/double_parsedouble.htm Also the Double.parseDouble is what you are importing at the start of the code.