# how do I find the Zc for a 70% confidence level?this is a statistic inferential problem

*print*Print*list*Cite

### 1 Answer

The critical zc value for a 70% confidence interval is required. The values in a standard normal table that can be found in the link given below, gives the probability that a variable lies between 0 and x.

For a 70% confidence interval 0.35 lies to the left of the z = 0 and 0.35 lies to the right of z = 0.

Find the value of z that corresponds to 0.35 from the table.

This is approximately equal to 1.003.

**The required critical values are approximately z = -1.003 and z = 1.003**

**Sources:**