Understanding Uninitialized Variables.....Please co-operate with me to write codes

Tell us what’s happening:

Your code so far

// Initialize these three variables
var a="myVar";
var b ;
var c;

if (b === 15) {
    b = "defined";
} else {
    b = "undefined";

// Do not change code below this line

a = a + 1;
b = b + 5;
c = c + " String!";

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Link to the challenge:

What is your question?

I have to do as per question “b should be defined and evaluate the value 15”
how can I do this?

Well, just like a = “myVar” , b needs to equal 15.

If I write b=15,code can’t run too.

It tells you what a, b and c should be at the end of the instructions, you needs to fill those values in.

a should not be "myVar", for example, that’s not the value it asks you for. b should not be 15, that’s just the value it is after you add 5 to it.

You should assign a value for b such that it adds up to 15 !