Each year advertisers spend billions of dollars purchasing commercial time on network television. In the first 6 months of one year, advertisers spent $1.1 billion. Who were the largest spenders? In a
Recent article, the top 10 leading spenders and how much each spent (in million of dollars)were
Listed: $$\begin{array} { l r l l }
\text { Company A } & \$ 72 & \text { Company F } & \$ 27.3 \
\text { Company B } & 63.6 & \text { Company G } & 25 \
\text { Company C } & 57.3 & \text { Company H } & 23.8 \
\text { Company D } & 54 & \text { Company I } & 23.1 \
\text { Company E } & 31.1 & \text { Company J } & 19.2
\end{array}$$ Calculate the sample variance.
A)391.238
B)3883.082
C)1919.040
D)2141.564

Question

Each year advertisers spend billions of dollars purchasing commercial time on network television. In the first 6 months of one year, advertisers spent $1.1 billion. Who were the largest spenders? In a
Recent article, the top 10 leading spenders and how much each spent (in million of dollars)were
Listed: $$\begin{array} { l r l l } 
\text { Company A } & \$ 72 & \text { Company F } & \$ 27.3 \
\text { Company B } & 63.6 & \text { Company G } & 25 \
\text { Company C } & 57.3 & \text { Company H } & 23.8 \
\text { Company D } & 54 & \text { Company I } & 23.1 \
\text { Company E } & 31.1 & \text { Company J } & 19.2
\end{array}$$ Calculate the sample variance.
A)391.238
B)3883.082
C)1919.040
D)2141.564

Quizplus · Accepted Answer

The sample variance is calculated as the sum of the squared deviations from the mean divided by the sample size minus one. The mean is calculated as the sum of the values divided by the sample size. In this case, the mean is (72 + 63.6 + 57.3 + 54 + 31.1 + 27.3 + 25 + 23.8 + 23.1 + 19.2) / 10 = 400 / 10 = 40. The squared deviations from the mean are (72 - 40)^2 + (63.6 - 40)^2 + (57.3 - 40)^2 + (54 - 40)^2 + (31.1 - 40)^2 + (27.3 - 40)^2 + (25 - 40)^2 + (23.8 - 40)^2 + (23.1 - 40)^2 + (19.2 - 40)^2 = 1024 + 518.4 + 302.5 + 196 + 78.4 + 169 + 225 + 262.4 + 285.6 + 435.6 = 3912.5. The sample variance is therefore 3912.5 / (10 - 1) = 3912.5 / 9 = 434.722.

Each Year Advertisers Spend Billions of Dollars Purchasing Commercial Time