Ch$2,$ Problem $40$: Formulation

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Write down the formulation in the answer box below.$$

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Make sure the following four components are included:

Variable definitions:

Use a separate line for variable;Start each variable definition with "Let";

Example: Let x$1$ denote $...$

Specify the units.

Example: number of bags, gallons of a liquid, pounds $($lbs$)$ of flours, etc.

An objective function:

Start with either "max Z$="$ or "min Z$="$; Include only linear terms of decision variables after $``=".$

A set of constraints:

Start with $"$s$.$t$."$ for the $1$st constraint;$$Left$-$hand$-$side $($LHS$)$ of each constraint should only include linear terms of decision variables;Right$-$hand$-$side $($RHS$)$ of each constraint should only have numbers;Do not include $``$s$.$t$."$ for other constraints.

A set of variable restrictions:

Start with "and";Group variable restrictions if they are all non$-$negatively restricted.

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