Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
Farfield Travel and Lacket Travel are two travel companies that organise overseas tours. The numbers of holidays arranged in one particular week are shown in the table below, along with the means and standard deviations of the prices.
(i)[2]
Calculate the mean price of all $51$ holidays.
(ii)[5]
Let the prices of individual holidays with Farfield Travel be $x_F$ and those with Lacket Travel be $x_L$. By first working out $\sum x_F^2$ and $\sum x_L^2$, find the standard deviation of the prices of all $51$ holidays.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Correct approach for the mean, for example $\frac{30\times1500 + 21\times2400}{51}$.” …