The following table describes the results of roadworthiness tests of Ford Focus cars that are three years old (based on data from the Department of Transportation). The random variable x represents the number of cars that failed among six that were tested for roadworthiness:
$\begin{array} { | c | c | }
\hline \boldsymbol { x } & \boldsymbol { P } ( \boldsymbol { x } ) \
\hline 0 & 0.377 \
\hline 1 & 0.399 \
\hline 2 & 0.176 \
\hline 3 & 0.041 \
\hline 4 & 0.005 \
\hline 5 & 0 + \
\hline 6 & 0 + \
\hline
\end{array}$
Find the probability of getting three or more cars that fail among six cars tested.
A) 0.005
B) 0.046
C) 0.048
D) 0.222

Question

The following table describes the results of roadworthiness tests of Ford Focus cars that are three years old (based on data from the Department of Transportation). The random variable x represents the number of cars that failed among six that were tested for roadworthiness: 
$\begin{array} { | c | c | } 
\hline \boldsymbol { x } & \boldsymbol { P } ( \boldsymbol { x } ) \
\hline 0 & 0.377 \
\hline 1 & 0.399 \
\hline 2 & 0.176 \
\hline 3 & 0.041 \
\hline 4 & 0.005 \
\hline 5 & 0 + \
\hline 6 & 0 + \
\hline
\end{array}$
 Find the probability of getting three or more cars that fail among six cars tested.
A) 0.005
B) 0.046
C) 0.048
D) 0.222

Quizplus · Accepted Answer

To find the probability of getting three or more cars that fail, add the probabilities for 3, 4, 5, and 6 failures: 0.041 + 0.005 + 0 + 0 = 0.046.

The Following Table Describes the Results of Roadworthiness Tests of Ford