## Math For Social Sciences. Practice Exam

1. Use the elimination method to solve each of the following systems:
2. Let , , and .
• Give the dimensions of each matrix, and identify any square, column, or row matrices.
• Find the following if possible:
• BC.
• CA.
3. Use the Gauss Jordan method to solve the following system:

4. Use the method of matrix inverses to solve the following system:

5. A 45-year-old man puts \$1,000 in a retirement account at the beginning of each quarter until he reaches the age of 60 and makes no further deposits. If the account pays 11% interest compounded quarterly, how much will be in the account when the man reaches age 60?
6. A speculator agrees to pay \$15,999 for a parcel of land; this amount, with interest, will be paid over 4 yr, with semiannual payments, at an interest rate of 10% compounded semiannually. Find the amount of each payment.

Formulas

• Future value for simple interest:

• Future value for compound interest:

• Future value of an ordinary annuity:

• Future value of an annuity due:

• Present value of an annuity:

• Amortizing a loan: