To find the joint relative frequency of elementary age students who prefer winter, you need to divide the number of elementary age students who prefer winter by the total number of students surveyed.
From the table:
- The number of elementary age students who prefer winter = 84
- The total number of students surveyed = 251
Now, you calculate the joint relative frequency:
\[ \text{Joint relative frequency} = \frac{\text{Number of elementary age students who prefer winter}}{\text{Total number of students}} = \frac{84}{251} \]
Next, we convert this to a percentage by multiplying by 100:
\[ \text{Percentage} = \left( \frac{84}{251} \right) \times 100 \approx 33.475 % \]
Rounding this to the nearest whole number gives:
\[ \text{Percentage} \approx 33% \]
Thus, the joint relative frequency of elementary age students who prefer winter is 33%.