# Problem 2: Even Fibonacci Numbers. Vague instruction?

Tell us what’s happening:
I am not understanding what the instruction is saying.

How is this test case returning… `fiboEvenSum(10) should return 188`?

When the sum of even numbers in the first 10 numbers come out to be…

1, 2, 3, 5, 8, 13, 21, 34, 55, 89. 2 + 8 + 34 = 44.

Or If I add together even indexes…

1, 2, 3, 5, 8, 13, 21, 34, 55, 89. 1 + 3 + 8 + 21 + 55 = 88.

``````
function fiboEvenSum(number) {
// You can do it!2+8+34+
return true;
}

fiboEvenSum(10);
``````

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36`.

The starting sequence is off by 1 or 2 if I’m remembering correctly. You must account for that offset if you want to pass the challenge.

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I agree there is room for improvement in the instructions.

I think they want the sum of the even terms only so you must find the first 11 even terms ( if the parameter says index is 10) in the series
1 2 3 5 8 13 21 34 55 89 144

and add the even numbers only:
2+8+34+144 = 188

Thanks, Looks like I have to increment the parameter by one then.

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