<PRE><B>Question 1140530</B>
19% of brand A tires go flat after 1 year means that 100 - 19 = 81% do not go flat after 1 year
:
Note 81% = 0.81
:
use the binomial probability distribution
:
Probability (P) (k successes in n trials) = nCk * p^k * (1-p)^(n-k), where nCk = n! / (k! * (n-k)!)
:
p = 0.81, n = 24, k = 10
:
P (10 tubes not going flat in 1 year out of 24 tubes) = 24C10 * (0.81)^10 * (1-0.81)^(24-10) = 0.00001905175
:
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