Answer
P(13 or 14) = 0.2103
Interpretation: The probability that 13 or 14 people feel that the state of morals is poor is 0.2103. If we carry out 100 trials of this experiment, we expect that approximately 21 trials will result in 13 or 14 people feeling that the state of morals is poor.
Work Step by Step
Using the formula ${n}\choose{x}$ $\cdot$ $p^{x}$ $\cdot$ $q^{n-x}$:
P(x = 13)
= ${25}\choose{13}$ $\cdot$ $0.45^{13}$ $\cdot$ $0.55^{25-13}$ = 0.1236
P(x = 14)
= ${25}\choose{14}$ $\cdot$ $0.45^{14}\cdot 0.55^{25-14}$ = 0.08671
Therefore, P(13 or 14) = 0.1236 + 0.08671 = 0.2103
