At a local fitness center, members pay a $10 membership fee and $4 for each aerobics class. Nonmembers pay $6 for each aerobics class. For what number of aerobics classes will the cost for members and nonmembers be the same?

Abank manager wants to encourage new customers to open accounts with principals of at least $2 comma 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! "?