To determine if the quantities in the data table are in a proportional relationship, we need to check if the ratio of the cost of tickets to the number of adults is constant.
Let's calculate the ratio of Cost of Tickets to Number of Adults for each entry:
- For 1 adult: \( \frac{75}{1} = 75 \)
- For 2 adults: \( \frac{150}{2} = 75 \)
- For 3 adults: \( \frac{225}{3} = 75 \)
- For 5 adults: \( \frac{375}{5} = 75 \)
- For 10 adults: \( \frac{750}{10} = 75 \)
- For 100 adults: \( \frac{7500}{100} = 75 \)
Since the ratio of Cost of Tickets to Number of Adults is constant (75) for all entries, the quantities in the data table are in a proportional relationship.
Therefore, the answer is 1.