Answer:
P(x<=5) = 0.6164
Step-by-step explanation:
The probability of getting a four in general throw = 1/6
Probability of getting 4, 5 times in a throw of 30 roll of cubes
= (1/6) ^5
X P(X)
P ( X = 0) C (30,0) * 0.167^0 * ( 1 - 0.167)^30= 0 0.0042
P ( X = 1) = C (30,1) * 0.167^1 * ( 1 - 0.167)^29= 1 0.0253
P ( X = 2) = C (30,2) * 0.167^2 * ( 1 - 0.167)^28= 2 0.0733
P ( X = 3) = C (30,3) * 0.167^3 * ( 1 - 0.167)^27= 3 0.1368
P ( X = 4) = C (30,4) * 0.167^4 * ( 1 - 0.167)^26= 4 0.1847
P ( X = 5) = C (30,5) * 0.167^5 * ( 1 - 0.167)^25= 5 0.1921
P(x<=5) = 0.6164