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# Unexpected identifier error given to me with next challenge

Not sure what I'm doing wrong:

```  const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"];
let numberOf503;

// numberOf503 should be: 3
numberOf503 = phoneNumbers.reduce( (sum, phoneNumber) => {
if phoneNumber.startsWith('(503') {
sum += 1;
return sum;
}
return sum;
}, 0);
```

Hi Rick,

You're missing the parenthesis around the conditional for your if statement. There's also a tiny typo -- a missing "s" on the end of `phoneNumbers` on line 6.

If you add in the parenthesis and correct the typo your code works great:

```numberOf503 = phoneNumbers.reduce( (sum, phoneNumbers) => {
if (phoneNumbers.startsWith('(503')) {
sum += 1;
return sum;
}
return sum;
}, 0);
```

I was thinking the if condition wouldn't need parentheses, so I didn't think to try that. It works once I add those. Thanks, Cameron!

The 's' actually isn't needed for the formal argument of the callback. Since it represents a single element in the array, rather than the entire array being passed each time it iterates, I named it in the singular. This is the pattern I've seen in examples, so I just followed that. But it could be named whatever as long as it matches what is used in the body of the callback.

My mistake! I was a little too hasty and when I rewrote your if statement I put an 's' on the end myself then noticed a mismatch (of my own creation!). You're absolutely correct, good catch :)

No problem. You're quick response was very helpful!