Final answer:
To find the N end of month payment and the last payment Q for a loan, one typically uses the formula for an ordinary annuity considering the interest rate and frequency of payments. For Tammar's case with a 5.4% interest rate and a differing number of payments, precise calculations are required which aren't provided here.
Step-by-step explanation:
To find the N end of month payment for Tammar's car financed at Friendly Finance at a nominal interest rate of 5.4% convertible monthly, you would use the formula for an ordinary annuity to solve for the number of payments. However, since the exact formula and calculations are not provided in the details, we cannot provide a direct answer.
The last payment (Q) depends on the balance remaining after the penultimate payment has been made. As the balance may not be a full payment of $345, it will typically be less and depends on the payments made so far and the interest accrued.
Finally, if Tammar only makes 24 payments on the $9600 loan at 5.4% interest convertible monthly, the size of each payment would be different from $345 to finish paying off the loan in exactly two years. This calculation would again involve the ordinary annuity formula, adjusting for a smaller number of payments at a potentially higher monthly cost.