Let us assume that total amount of Nathan's allowance = x Amount of money deposited by Nathan into his savings account = 7x/9 Remaining amount that Nathan spent = $2.50 Now we have to get to the equation for solving the question asked. 7x/9 + 2.50 = x 7x + (9 * 2.50) = 9x 7x + 22.50 = 9x 22.50 = 9x - 7x 22.50 =2x x = 22.50/2 = 11.25 So $11.25 is the total allowance of Nathan. Then The amount of money deposited by Nathan in savings account = (7/9) * 11.25 = 78.75/9 = 8.75 So Nathan deposits $8.75 in his savings account. <span />