## Elementary Technical Mathematics

$\frac{5}{16}$ in
To find the remaining thickness, subtract the depth of the holes from the depth of the base. Convert fractions to least common denominator and subtract the numerators. $\frac{7}{8}-\frac{9}{16}=\frac{7\times2}{8\times2}-\frac{9}{16}=\frac{14}{16}-\frac{9}{16}=\frac{5}{16}$