Answer:
Given :
The probability of success, $p=0.40$
The sample size, $n=12$
Solution :
→ The probability that exactly 10 of the invoices will be paid within ten working days :
$$P(x = 10) = \binom{n}{x} p^x (1 – p)^{n – x} \bigg|_{x=10}$$ $$= \binom{12}{10} 0.4^{10} (1 – 0.4)^{12 – 10}$$ $$= 0.002491$$
