Boy, I sure would love it if someone could help me figure this out. My professor has created some code that's a loop for enter numbers. I need to add code to make the program figure averages and standard deviation. I've added the formulas as I believe they should be, and the program runs, but when I test the program with some small numbers I can do in my head, the average and deviation is wrong. Here's the code, stripped of pretty formatting....

Code:// Program Abstract: the purpose of this program is to determine the average and standard deviation of input numbers // Input Required: list of numbers // Output Desired: program will output the list of numbers, // average and standard deviation of each number // ============================================================================= #include <conio.h> #include <fstream.h> #include <iomanip.h> #include <iostream.h> #include <math.h> //============================================================================== // variable declarations // alphabetized variable dictionary // ========================================================================= // d is data // i is spacing // m is average // n is count // reply stores user's answer to queries // s is standard deviation // x is sum int main() { double d, i, m, n, s, x; double average, stddev, sum, sumsqr; char reply; ofstream fout; fout.open ("prompt.txt"); // introduce the program to determine average and // standard deviation of a list of numbers //============================================================================== cout << setw (61) << "Program for average and standard deviation"; // press any key to continue cout << setw (52) << "Press RETURN to continue"; getchar(); // run program until user is done // loop for data entry, calculates sum and counter, ends after last while do { // setting beginning numbers to 0 n = 0; x = 0; sumsqr = 0; // loop B check and correct data entry do { clrscr (); // prompt the user for the next data cout << setw (61) << "Enter next data, enter -1 to end data stream"; cout << ": "; cin >> d; do { clrscr (); // echo print data read cout << setw (37) << "Is " << d << " correct?"; cout << endl << endl << endl; // query the user for correctness of input data cout << setw (55) << "Enter y for yes or n for no: "; // input response to query cin >> reply; tolower(reply); } while(reply!='n' && reply!='y'); if(reply=='y') { ++n ; x += d; sumsqr += d * d; // record verified data in output textfile fout << d << endl; } } while (d != -1); // calculate average if ( n > 0 ) m = x / n; else m = 0 ; // press any key to continue cout << setw (52) << "Press RETURN to continue"; getchar(); // calculate standard deviation if ( n > 1 ) s = sqrt ((n * sumsqr - x * x) / (n * (n - 1))) ; else s = 0; clrscr (); cout << setw (50) << "The average is: " << m; cout << setw (50) << "The standard deviation is: " << s; // press any key to continue cout << setw (52) << "Press RETURN to continue"; getchar(); do { clrscr (); // query user for another input data cout << setw (55) << "Is there another set of data?"; cout << setw (55) << "Enter y for yes or n for no: "; cin >> reply; tolower(reply); } while ((reply != 'n') && (reply != 'N') && (reply != 'y') && (reply != 'Y')); } while ((reply == 'y') || (reply == 'Y')); fout.close (); return 0; }