Statistics
2110013505
Level:
C
The following scatter plots represent visualisations of relationships of two continuous variables. Choose the plot, which represents visualisation of a relationship of two variables with the lowest absolute value of the correlation coefficient.
2010013504
Level:
A
The average price of a pork meat increased by \(15\%\) in the year \(2018\), by \(13\%\) in the year \(2019\) and by \(28\%\) in the year \(2020\). Find the average percentage growth of the price of the pork meat per one year in the period \(2017\)-\(2020\). Round your result to the nearest percent.
\(18\%\)
\(19\%\)
\(20\%\)
\(17\%\)
2010013503
Level:
A
Four seamstresses sew doll dresses in a sheltered workshop. During the six-hour working hours, the first seamstress sewed \(4\) dresses, the second \(5\), the third \(7\) and the fourth \(4\) dresses. What was the average time needed to sew one dress on this day?
\( 1\,\mathrm{h}\ 12\,\mathrm{min} \)
\( 1\,\mathrm{h}\ 20\,\mathrm{min} \)
\( 1\,\mathrm{h}\ 10\,\mathrm{min} \)
\( 1\,\mathrm{h}\ 24\,\mathrm{min} \)
2010013502
Level:
A
The annual production of a business is recorded in the following table. Find the compound annual rate of decline in production for a given period \( 2017 \) - \( 2020 \). (I.e., the average annual coefficient of the production decline, i.e., the ratio that provides a constant decline rate over the time period.) Round the result to four decimal places. \[
\begin{array}{|c|c|c|c|c|} \hline \text{Year} & 2017 & 2018 & 2019 & 2020 \\\hline \text{Production (pcs)} & 55\: 000 & 50\: 000& 47\: 000 & 45\: 000 \\\hline
\end{array}\]
\( 0.9353 \)
\( 0.9225 \)
\( 0.9898 \)
\( 0.9535 \)
2010013501
Level:
A
Two years ago, a family business reported gross profit of \(3.5\) million euros. During the pandemic, the company got into trouble so that its last year gross profit fell by \(20\%\) and its gross profit of this year was \(1\) million euros lower than of the last year. What was the average annual decrease in the gross profit reported by the company during the priod under review? Round the result to the tenth of a percent.
\(28.3\%\)
\(27.9\%\)
\(26.7\%\)
\(28.2\%\)
2010018105
Level:
C
The values of variables \( x \) and \( y \) are listed in the following table and visualized in the next graph. Calculate the correlation coefficient of \( x \) and \( y \) and round it to four decimal places.
\[ \begin{array}{|c|c|c|c|c|c|} \hline x & 1 & 2 & 3 & 4& 4.5 \\\hline y & 6 & 4 &5 & 3 & 3.5 \\\hline \end{array} \]
\(-0.8120\)
\(-0.8211\)
\(-0.8305\)
\(-0.8021\)
2010018104
Level:
A
The table shows the heights of ten girls. Determine the median of this data file.
\[
\begin{array}{|l|c|c|c|c|c|c|c|c|c|} \hline 171 & 173 & 160 & 162 & 165 & 158 & 175& 163&168&169\\\hline\end{array}
\]
\(166.5\)
\(166\)
\(168\)
\(167.5\)
2010018103
Level:
A
In February 2021, Aneta recorded an outdoor temperature in Ostrava-Poruba, always measured at \(2\) p.m. The results in \(^{\circ}\mathrm{C}\) are shown in the following table:
\[
\begin{array}{|l|c|c|c|c|c|c|c|c|} \hline
\text{Day} & 1. & 2. & 3. & 4. & 5. & 6. & 7. & 8. \\\hline \text{Temperature }(^{\circ}\mathrm{C}) & -1 & 3 & 7& 8 & 3 & 0 & -4 & -5 \\\hline \\\hline
\text{Day} & 9. & 10. & 11. & 12. & 13. & 14. & 15. & 16.\\\hline \text{Temperature } (^{\circ}\mathrm{C}) & -4 & -3 & -6 & -4 & -3 & 2 & -2 & 0\\\hline \\\hline
\text{Day} & 17. & 18. & 19. & 20. & 21. & 22. & 23. & 24. \\\hline \text{Temperature } (^{\circ}\mathrm{C}) & 3 & 8 & 4 & 5 & 5 & 8 & 5 & 16 \\\hline \\\hline
\text{Day} & 25. & 26. & 27. & 28. & & & & \\\hline \text{Temperature } (^{\circ}\mathrm{C}) & 15 & 15 & 6 & 8 & & & & \\\hline \end{array}
\]
Determine the mode of the recorded temperatures.
\(8\,^{\circ}\mathrm{C}\)
\(3\,^{\circ}\mathrm{C}\)
\(-3\,^{\circ}\mathrm{C}\)
\(-4\,^{\circ}\mathrm{C}\)
2010018102
Level:
A
The same component is manufactured simultaneously on two differently powerful machines. The first one makes \(1\) component in \(20\) minutes, the second one makes the same component in \(10\) minutes. We are interested in how long it takes on average to produce \(1\) component using these two machines. What type of average do we use for the calculation?
Harmonic mean
Geometric mean
Arithmetic mean
Weighted arithmetic mean