Question

Gray cast iron blocks of size $\text{100 mm × 50 mm × 10 mm}$ with a central spherical cavity of diameter 4 mm are sand cast. The shrinkage allowance for the pattern is 3%. The ratio of the volume of the pattern to volume of the casting is

• A. 1.09

Answer 1

The correct option is A 1.09
$\text{Ratio of volume of pattern to casting}$

$=\frac{\left[\right(1.03\times 100)\times (1.03\times 50)\times (1.03\times 10\left)\right]-\frac{4}{3}\pi {\left(2.06\right)}^3}{(100\times 50\times 10)-\frac{4}{3}\pi {\left(2\right)}^3}$

$=1.09$