HP 35s HP 35s scientific calculator - User Guide - Page 267

Flags Used: None. Program Instructions: 1. Key in the program routines; press  when done. 2. Press S to start entering new data. 3. Key in xi -value (data point) and press . 4. Key in fi -value (frequency) and press . 5. Press  after VIEWing the number of points entered. 6. Repeat steps 3 through 5 for each data point. If you discover that you have made a data-entry error (xi or fi) after you have pressed  in step 4, press U and then press  again. Then go back to step 3 to enter the correct data. 7. When the last data pair has been input, press G to calculate and display the grouped standard deviation. 8. Press  to display the weighted mean of the grouped data. 9. To add additional data points, press  and continue at step 3. To start a new problem, start at step 2.Variables Used: X F N S M i Register -27 Register -28 Register -30 Example: Data point. Data-point frequency. Data-pair counter. Grouped standard deviation. Weighted mean. Index variable used to indirectly address the correct statistics register. Summation Σfi. Summation Σxifi. Summation Σxi2fi. Enter the following data and calculate the grouped standard deviation. Statistics Programs 16-21