## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$\frac{11}{12}\times\frac{12}{11}=\frac{11\times12}{12\times11}=\frac{121}{121}$ The numerator and denominator have a common factor of 121. Therefore, $\frac{121}{121}=\frac{121\div121}{121\div121}=\frac{1}{1}=1$. In general, the product of a number and its reciprocal will be 1.