Question 3
Rio wants a 20-dollar aquarium and may use only one coupon: save 10 dollars on an eligible purchase, or take 40% off. What is the least he can pay?

The source English says purchases above 15 dollars; the printed coupon and Vietnamese say 15 dollars or more. A 20-dollar purchase qualifies under either reading.

The source English says purchases above 15 dollars; the printed coupon and Vietnamese say 15 dollars or more. A 20-dollar purchase qualifies under either reading.