How accurately should I store latitude and longitude?

Question

I was reading this question here:

What datatype to use when storing latitude and longitude data in SQL databases?

And it seems the general consensus is that

Answer 1

+----------------+-------------+
|    Decimals    |  Precision  |
+----------------+-------------+
|    5           |  1m         |
|    4           |  11m        |
|    3           |  111m       |
+----------------+-------------+

If you want 50ft (15m) precision go for 4 digits. So decimal(9,6)