Nathan deposited 7/9 of his allowance into his savings account. He spent the remaining amount, or $2.50. How much did Nathan deposit into his savings account.

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.