## Basic College Mathematics (10th Edition)

Estimate: 2$\times$7$\times$1=14 Exact: $21\frac{3}{8}$
$2\frac{1}{4}.7\frac{1}{8}.1\frac{1}{3}$ First we need to find Estimate: $2\frac{1}{4}$ rounded to 2 $7\frac{1}{8}$ rounded to 7 $1\frac{1}{3}$ rounded to 1 2$\times$7$\times$1=14 (Estimate) Now we need to find Exact: $2\frac{1}{4}.7\frac{1}{8}.1\frac{1}{3}$ = $\frac{9}{4}\times\frac{57}{8}\times\frac{4}{3}$ = $\frac{9\times57\times4}{4\times8\times3}$ = $\frac{3\times57}{8}$ = $\frac{171}{8}$ = $21\frac{3}{8}$