This:
Code:
	if( y == 24){
	cout << "Wow, you must be Nostradamus reincarnated.\n";
	}
	else
		if (y < 24-11){
		cout << "You're way off, don't bother trying again\n";
		}
		else
			if (y > 21+11){
			cout << "What were you thinking?\n";
			}
			else
				if (y >= 24-10){
				cout << "You're warming up\n";
				}
				else
					if (y <= 24+10){
					cout << "You're warming up\n";
					}
					else
						if (y <= 24+5){
						cout << "You're burning up\n";
						}
						else
							if (y >= 24-5){
							cout << "You're burning up\n";
							}
Is more conventionally written as:
Code:
if (y == 24) {
    cout << "Wow, you must be Nostradamus reincarnated.\n";
}
else if (y < 24-11){
    cout << "You're way off, don't bother trying again\n";
}
else if (y > 21+11){
    cout << "What were you thinking?\n";
}
else if (y >= 24-10){
    cout << "You're warming up\n";
}
else if (y <= 24+10){
    cout << "You're warming up\n";
}
else if (y <= 24+5){
    cout << "You're burning up\n";
}
else if (y >= 24-5){
    cout << "You're burning up\n";
}
It looks like you just need to add:
Code:
srand(time(0));
int x = rand() &#37; 100; // An example for an integer in the range [0, 100)
Then change your literal 24 to x.