# Thread: Help in statistics for my exams with z calculations

1. ## Help in statistics for my exams with z calculations

Hi guys,nice to meet you,its my first time here(Sry for my english) !!

In some days i will be examed on statistic 2 and i have problem with the following problems :

My teacher says to answer if the following problems are true or false and to explain why(to prove it with calculations)

• 2 *z 0.035 = z 0.070
• z 0.05 >z 0.07
• z0.035 > t32 0.035
• z0.035 = 0.5*Z0.070

How i solve them ?
Thank you.

2. ## Re: Help in statistics for my exams with z calculations

Do you not know what the "z- statistic" is? It would be very strange for your teacher to give you problems like this if you don't. It would be strange for you to be in "Statistics 2" but not have learned that in "Statistics 1".

The z-statistic is the statistic (variable) in the standard normal distribution. You cannot calculate $z_{0.070}$ (there is a formula but it involves an integral that does not have an elementary "anti-derivative), you need to look it up in a table or some calculators (those designed for statistics work) gave a "z-statistic" key. Your text book probably has a table but Wikipedia has one, together with a discussion of how to use it, here:
https://en.wikipedia.org/wiki/Standard_normal_table