[Toothbrush]

Hey guys

Basically,I just want to know HOW the difference tables work. Let me give an example:

My Z value came to 0.3846, and so did the mark scheme's. Then, when I went to the tables, I looked at 0.38, which is 0.6480, and added the value at 5 as i thought 0.0046 should be rounded. That gave an overall value of 0.6499.

The mark scheme, however, had the same result as me (0.3846) for Z, yet had 0.6497- there isnt even a 17 value in the differences table!

[haggishurler]

If you want to use it for one more decimal place you add it for example 0.8000 and then in the differences table you find the third decimal for instance 3 follow it down to the value in line with the first decimal and add it like so. IIf it is 15 then you get 0.8015. however i want to know what to do if you need another decimal place after that I have been looking at the mark schemes and they require more accuracy.
Anyone able to help me out?