Natasha starts with $45 in her savings account, and each month she adds $6. Sal starts with $55 in his savings account, and each month he adds $4.
To find out how much money Natasha has after a certain number of months, we need to determine how many times she adds $6 to her initial amount and then add that to her starting amount.
Let's say she adds $6 for n number of months.
So her total amount after n months will be:
$45 + $6*n
Similarly, to find out how much money Sal has after a certain number of months, we need to determine how many times he adds $4 to his initial amount and then add that to his starting amount.
Let's say he adds $4 for m number of months.
So his total amount after m months will be:
$55 + $4*m