How do you use present value tables to calculate the present value of a lump sum and an ordinary annuity, and what key variables must you identify before using these tables?
To use present value tables, first identify the interest rate (r) and the number of periods (n). For a lump sum, use the present value of \$1 table: find the factor at the intersection of n and r, then multiply it by the future lump sum amount. For an ordinary annuity, use the present value of an ordinary annuity of \$1 table: find the factor for n and r, then multiply it by the annuity payment. If payments are semiannual, divide the annual interest rate by 2 and multiply the number of years by 2 before using the tables.