"João vendeu sua bicicleta a 360 reais, o que era 80% do que ele havia pago. Por quanto ele deveria ter vendido para ter um lucro de 20%?"​

Becca wants to mix fruit juice and soda to make a punch. she can buy fruit juice for $3 a gallon and soda for $4 a gallon. if she wants to make 28 gallons of punch at a cost of $3.25 a gallon, how many gallons of fruit juice and how many gallons of soda should she buy?