Find the amount paid for the loan. $2400 at 10.5% for 5 years

I think you mean the total mount paid for the loan.
There is a formula for that. (See attached).
principal = 2,400
n = number of payments = 5 * 12 months = 60
rate = 10.5 / 1,200 = .00875
Loan Cost Total = (r*p*n) / (1 - (1 +r)^-n)
Loan Cost Total = .00875 * 2,400 * 60 / (1 -(1.00875^-60)
Loan Cost Total = 1,260 / (1 - 0.5929077624 )
Loan Cost Total = 1,260 / 0.4070922376
Loan Cost Total = 3,095.12