Question

Your current account balance is $215. You have $322 of expenses each month. Your income is $444 per month. How long will it take you to accumulate a balance of $1000 in your account.

Answer 1

By doing some simple math, we find that your net income is $122 every month. So, we must add $122  to $215 and count up in the months as we go.
$215+$122= $337          (month 1)
$337+$122=$459           (month 2)
$459+122=$581             (month 3)
$581+$122=$703           (month 4)
$703+$122=$822           (month 5)
$822+$122=$947           (month 6)
$947+$122=$1,069        (month 7)

So on month 7 we finally got past $1,000!

Answer 2

Let y be the balance in your account. Let x be the number of months.

y = 215 + (444-322)x = 215 + 122x

1000 = 215 + 122x
785 = 122x
x = 6.43 months