Type the number of data values into the textbox and then press the enter key or click on the "Enter Data" button. Then enter the data values one at a time, pressing the enter key or clicking the "Enter Data" button after each entry.
When all of the data is entered, a black triangular "balance point" will appear in the center of the histogram and it will "teeter" on that balance point. Click and drag the triangle to where you estimate the mean to be. When you drag to the actual mean, the histogram will balance perfectly and the value of the mean will be reported on the status line.
Once you have balanced the histogram on the mean, you will be prompted that you may change a data value. You may do this in one of two ways. To make a change within the given range of the data, simply click and drag the data point to a new location. To make a change outside the current range, click on the data point you want to change. It will disappear and you will be prompted to enter a new value in the textbox. After doing so, the histogram will be redrawn and you will have to rebalance it.
By repeating this process, you may change as many data values as you need. By clicking on the "New Histogram" button you may start over with a new data set at any time.