What you have, 0.92, would be correct if we were rounding to 2 decimal places.

We need the number rounded to 4 decimal places.

To do this lets look at the first 5 decimal places:

# 0.9174311926605504587155963302752293577981651376146788991

If the fith decimal place is a 0,1,2,3 or 4, the 4th digit stays the same (called rounding down). If the 5th digit is a 5,6,7,8 or 9, the 4th digit is rounded up by 1.

For example, if the number was 0.91748, the result when rounded to 4 decimal places would be 0.9175 (note there are 4 digits after the decimal point.

When looking at your number we can see that because the 3 is below 5, the number should be rounded down, resulting in 0.9174

I hope this helped and that it wasn't too longwinded :)