The number 5

The number of hours per week the television is turned on is determined for each family in a sample. The mean of the data is 35 hours, and the median is 31.2 hours. Twenty-four families in the sample turned on the television for 20 hours or less for the week. The 6th percentile of the data is 20 hours.

Question: Approximately how many families are in the sample? Round your answer to the nearest integer.

Correct answer:

n =  333

Step-by-step explanation:

$$\begin{gathered} \mu =35 \\ m=31.2 \\ {p}_6=20 \\ q=6\%=\frac{6}{100}=\frac{3}{50}=0.06 \\ n\cdot q=20 \\ n\cdot 0.06=20 \\ 0.06n=20 \\ n=\frac{20}{0.06}=333.33333333 \\ n=\frac{1000}{3}\doteq 333.333333=333 \end{gathered}$$

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