## Basic College Mathematics (10th Edition)

Estimate: 5 - 2 = 3 Exact:$2\frac{5}{8}$
$5-2\frac{3}{8}$ First Lets Find Estimate: $2\frac{3}{8}$ rounds to 2 Now, $5-2\frac{3}{8}$ = 5 - 2 = 3 Now find Exact: $5-2\frac{3}{8}$ = $5-\frac{2\times8+3}{8}$ = $5-\frac{19}{8}$ = $\frac{5\times8}{1\times8}-\frac{19}{8}$ (LCM of 1 & 8 is 8) = $\frac{40}{8}-\frac{19}{8}$ = $\frac{40-19}{8}$ = $\frac{21}{8}$ = $2\frac{5}{8}$