i$)$ T R & C Engineering is planning to buy a couple of thousand bolts to be used in

their systems. The system requires highly reliable bolts. In case of a bolt failure,

the system repair cost is estimated to be $$15\mathrm{.}00.$ Two companies that use

different kinds of alloys in their products bid to supply the bolts. T R & C

Engineering decides to go for destructive testing using $20$ specimens. The

criterion used for testing is ultimate tensile strength measured in $kg\frac{f}{m}{m}^2.$ The

test data for both products are given in Table Q$7$b$.$ The lower specification limit

is $11kg\frac{f}{m}{m}^2,$ and the purchase quantity is $20000$ units. The unit costs of

products A and B are $$0\mathrm{.}14$ and $$0\mathrm{.}13,$ respectively. Advise T R & C Engineering

about its purchasing decision.

Table Q$7$b: Ultimate Tensile Strength Data