Dave has 10 more marbles than emma. emma has m number of marbles. write a variable expression for the number of marbles that dave has

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!