#include <bits/stdc++.h>
#include <math.h>

using namespace std;

// In a certain plant, the time taken to assemble a car is a random
// variable, X, having a normal distribution with a mean of 20 hours
// and a standard deviation of 2 hours. What is the probability that a
// car can be assembled at this plant in:

// 1) Less than 19.5 hours?
// 2) Between 20 and 22 hours?

int main()
{
    int mean = 20;  // mu
    int stddev = 2; // sigma

    // Probability P(X <= x)
    auto normalCDF = [](double x, double mean, double stddev)
    {
        double val = (x - mean)/(stddev * sqrt(2));
        return 0.5 * (1 + (erf(val)));
    };

    // P(a <= X <= b) = P(a < X < b) = normalCDF(b) - normalCDF(a)

    double answer_1 = normalCDF(19.5, mean, stddev);
    double answer_2 = normalCDF(22, mean, stddev) - normalCDF(20, mean, stddev);

    cout << fixed << setprecision(3) << answer_1 << endl;    
    cout << fixed << setprecision(3) << answer_2 << endl;        
}