Harry made fruit punch using 2 parts orange juice to 2 parts soda water. the amount of soda water that harry used is directly proportional to the amount of orange juice he used. how many cups of orange juice should harry use with 18 cups of soda water?

Abank manager wants to encourage new customers to open accounts with principals of at least $2,500. he decides to make a poster advertising a simple interest rate of 3%. what must the principal be if the bank manager also wants to advertise that one can earn $10 the first month? can the poster correctly say, "open an account of $2 comma 500 and earn at least $10 interest in 1 month! "?