TĐH p=4/5 from math import comb

P(X>2)=P(X=3)+P(X=4)=kCn*p(k)*(1-p)^(n-k)

n=4 k1=3 k2=4 print(round(comb(n,k1)*pow(p,k1)*pow(1-p,n-k1)+comb(n,k2)*pow(p,k2)*pow(1-p,n-k2)),3) n=4 k1=1 k2=0 print(round(comb(n,k1)*pow(p,k1)*pow(1-p,n-k1)+comb(n,k2)*pow(p,k2)*pow(1-p,n-k2),3))

python3:

p = 4/5
n = 4


def binom(k, n, p):
    res = 1
    a = 1
    for i in range(1, n+1):
        a *= i
    b = 1
    for i in range(1, n-k+1):
        b *= i
    c = 1
    for i in range(1, k+1):
        c *= i
    return a/b/c * p**k * (1-p)**(n-k)


def prob(k):
    return binom(k, n, p)


if __name__ == '__main__':
    result = prob(3) + prob(4)
    print('%.3f' % result)

    result = prob(0) + prob(1)
    print('%.3f' % result)

from math import factorial as fact

Permutation

def permutation(n, r): return fact(n)/(fact(n-r))

Combinations

def combination(n, r): return permutation(n,r)/fact(r)

BINOMIAL DISTRIBUTION

def binomial_dist(n, x, p):

q = 1-p

return combination(n, x)*(p**x)(q*(n-x))

The rest you can do :)

Also make sure to put the zero

AAARGH you really need to round the answers in the solution checker, not just compare the files.

If you're solving this problem, you should ONLY output 3 decimals. The instructions are not clear.