The probability that the light bulb is defective is as follows.
[tex]P(defective)=0.15[/tex]On the other hand, the probability that the light bulb is not defective is as follows.
[tex]P(\text{not defective})=1-0.15=0.85[/tex]To identify the probabiliy that at least one is defective, we have the following:
[tex]\begin{gathered} P(\text{at least 1 is defective})=1-P(\text{5 are not defective}) \\ =1-(0.85)^5 \\ \approx1-0.443705 \\ \approx0.556295 \\ \approx55.6295\% \end{gathered}[/tex]Thus, the probability that at least one is defective is about 55.63%.
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