## How do you find confidence interval on calculator?

**Therefore, a z-interval can be used to calculate the confidence interval.**

- Step 1: Go to the z-interval on the calculator. Press [STAT]->Calc->7.
- Step 2: Highlight STATS. Since we have statistics for the sample already calculated, we will highlight STATS at the top.
- Step 3: Enter Data.
- Step 4: Calculate and interpret.

## How do you find a confidence interval on a TI 84 calculator without standard deviation?

Confidence Interval for a Mean, Standard Deviation Unknown

## How do you find the upper and lower bound of a confidence interval on a TI 84?

Upper and Lower Bounds of the T-Interval –

## How do you find confidence intervals?

Confidence Interval for a Proportion Example 2: Steps

Step 1: Divide your confidence level by 2: . 95/2 = 0.475. Step 2: Look up the value you calculated in Step 1 in the z-table and find the corresponding z-value. The z-value that has an area of .

## What is a statistically significant sample size?

Generally, the rule of thumb is that the larger the sample size, the more statistically significant it is—meaning there’s less of a chance that your results happened by coincidence.

## How do you find an unknown standard deviation?

Confidence Intervals: Example when the Population Standard

## How do you determine a sample size?

**How to Find a Sample Size Given a Confidence Interval and Width (unknown population standard deviation)**

- za/2: Divide the confidence interval by two, and look that area up in the z-table: .95 / 2 = 0.475.
- E (margin of error): Divide the given width by 2. 6% / 2.
- : use the given percentage. 41% = 0.41.
- : subtract. from 1.

## How do you find a 90% confidence interval on a TI 84?

How to find the confidence interval of the proportion in the TI-84