Answer:
8.8%
Step-by-step explanation:
Given that,
Cross-price elasticity between airline tickets and gasoline = 2.2
Price of the gasoline increases by 4%.
Therefore,
Cross-price elasticity = Percentage change in the quantity demanded of airline tickets ÷ Percentage change in the price of gasoline
2.2 = Percentage change in the quantity demanded of airline tickets ÷ 4%
2.2 × 4 = Percentage change in the quantity demanded of airline tickets
8.8% = Percentage change in the quantity demanded of airline tickets