Question

In 2002, France adopted the Euro as its currency, replacing the French Franc. At that time, one Euro was worth 0.90 in American currency. In Paris, France, a quart of milk costs 3 Euros. In Los Angeles, a quart of milk costs $1.65. In which city was the quart of milk more expensive?

Answer 1

Convert the Euros to dollars; the ratio is 1 euro : .90 dollar

Since the price for a quart of milk is higher in France than in MERICA, then it is more expensive there, than here.
P.S. You can convert from dollars to Euros, so long as you align the ratios.