1. The following table gives the frequency distribution of the number of hours each group of people out of 40 took to finish the same amount of work. \begin{tabular}{|c|c|} \hline Number of hours & \( \boldsymbol{f}_{i} \) \\ \hline \( 4-6 \) & 5 \\ \hline \( 7-9 \) & 7 \\ \hline \( 10-12 \) & 12 \\ \hline \( 13-15 \) & 10 \\ \hline \( 16-18 \) & 6 \\ \hline & \( n=40 \) \\ \hline \end{tabular} a) Find the mode, median and mean b) Find the range, variance and standard deviation 2. A random study, on samples, of the number of defective devices produced from two companies produced the following results \begin{tabular}{|l|l|l|l|} \hline & Defective Devices & \begin{tabular}{l} Non-defective \\ Devices \end{tabular} & Total \\ \hline Company A & \( \mathbf{3 0} \) & \( \mathbf{7 0} \) & 100 \\ \hline Company B & \( \mathbf{6 0} \) & \( \mathbf{1 5 0} \) & 210 \\ \hline Total & 90 & 220 & 310 \\ \hline \end{tabular} a) Give the joint probability table of the produced devices b) What is the probability that a manufactured device is defective? c) What is the probability that a manufactured device is from company B and non-defective? d) What is the probability that a manufactured device is from company A or company \( \mathrm{B} \) ? e) What is the probability that a device is defective if it is manufactured by company B?
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### Part 1: Frequency Distribution of Hours Worked #### a) Find the mode, median, and mean ** Show more…
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