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Finite State Machine

Mathematics · FE Reference Handbook section

Mathematics
3 formulas
10 exam-style examples
~51 min
All Mathematics lectures

Handbook notes for this section

Definitions and conditions exactly as the handbook states them.

  • A finite state machine consists of a finite set of states
  • A state (or truth) table can be used to represent the finite state machine.
  • Another way to represent a finite state machine is to use a state diagram, which is a directed graph with labeled edges.
  • The characteristic of how a function maps one set (X) to another set (Y) may be described in terms of being either injective,
  • An injective (one-to-one) relationship exists if, and only if,
  • A bijective relationship is both injective (one-to-one) and surjective (onto).

Core formulas for this FE topic

Definitions, applicability, units, assumptions and worked examples for each relation.

Worked exam-style examples

The four ways this section is written on the real exam — thoughts first, then equations, then substitution.

Example 1
Entries in a relation (adjacency) matrix — solve for matrix entries — Finite State Machine

a relation matrix linking survey stations to control points Given rows (elements of the first set) (n_r) = 7.0000; columns (elements of the second set) (n_c) = 10.0000, determine the matrix entries (E) in entries.

Given

  • rows(elementsofthefirstset)(nr)=7.0000rows (elements of the first set) (n_r) = 7.0000
  • columns(elementsofthesecondset)(nc)=10.0000columns (elements of the second set) (n_c) = 10.0000

Find

matrix entries (E), in entries

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for E:

    E=nrncE = n_r n_c
  3. Step 3 — List the givens: rows (elements of the first set) (n_r) = 7.0000, columns (elements of the second set) (n_c) = 10.0000.

  4. Step 4 — Substitute the given values:

    E=nrncE = n_r n_c
  5. Step 5 — Evaluate:

    E=70.0000 entriesE = 70.0000\ \text{entries}
  6. Step 6 — Check: returning E = 70.0000 entries to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=70.0000 entriesE = 70.0000\ \text{entries}

Why the other options are there

  • 140.0 — kept a factor of two that cancels in the correct rearrangement.
  • 35.0000 — dropped that same factor in the other direction.
  • 77.0000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 2
Entries in a relation (adjacency) matrix — solve for rows (elements of the first set) — Finite State Machine (2)

a finite state machine transition table stored as a Boolean matrix Given matrix entries (E) = 381.0 entries; columns (elements of the second set) (n_c) = 9.0000, determine the rows (elements of the first set) (n_r).

Given

  • matrixentries(E)=381.0entriesmatrix entries (E) = 381.0 entries
  • columns(elementsofthesecondset)(nc)=9.0000columns (elements of the second set) (n_c) = 9.0000

Find

rows (elements of the first set) (n_r)

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except n_r is given, so isolate n_r symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for n_r:

    nr=Encn_{r} = \dfrac{E}{n_c}
  3. Step 3

    Listthegivens:matrixentries(E)=381.0entries,columns(elementsofthesecondset)(nc)=9.0000List the givens: matrix entries (E) = 381.0 entries, columns (elements of the second set) (n_c) = 9.0000
  4. Step 4 — Substitute the given values:

    nr=381.0ncn_{r} = \dfrac{381.0}{n_c}
  5. Step 5 — Evaluate:

    nr=42.3333n_{r} = 42.3333
  6. Step 6 — Check: returning n_r = 42.3333 to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
nr=42.3333n_{r} = 42.3333

Why the other options are there

  • 84.6667 — kept a factor of two that cancels in the correct rearrangement.
  • 21.1667 — dropped that same factor in the other direction.
  • 46.5667 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 3
Entries in a relation (adjacency) matrix — solve for columns (elements of the second set) — Finite State Machine (3)

a relation matrix linking pipe nodes to demand nodes Given matrix entries (E) = 180.0 entries; rows (elements of the first set) (n_r) = 13.0000, determine the columns (elements of the second set) (n_c).

Given

  • matrixentries(E)=180.0entriesmatrix entries (E) = 180.0 entries
  • rows(elementsofthefirstset)(nr)=13.0000rows (elements of the first set) (n_r) = 13.0000

Find

columns (elements of the second set) (n_c)

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except n_c is given, so isolate n_c symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for n_c:

    nc=Enrn_{c} = \dfrac{E}{n_r}
  3. Step 3

    Listthegivens:matrixentries(E)=180.0entries,rows(elementsofthefirstset)(nr)=13.0000List the givens: matrix entries (E) = 180.0 entries, rows (elements of the first set) (n_r) = 13.0000
  4. Step 4 — Substitute the given values:

    nc=180.0nrn_{c} = \dfrac{180.0}{n_r}
  5. Step 5 — Evaluate:

    nc=13.8462n_{c} = 13.8462
  6. Step 6 — Check: returning n_c = 13.8462 to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
nc=13.8462n_{c} = 13.8462

Why the other options are there

  • 27.6923 — kept a factor of two that cancels in the correct rearrangement.
  • 6.9231 — dropped that same factor in the other direction.
  • 15.2308 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 4
Entries in a relation (adjacency) matrix — solve for matrix entries (case 2) — Finite State Machine (4)

a relation matrix linking survey stations to control points Given rows (elements of the first set) (n_r) = 19.0000; columns (elements of the second set) (n_c) = 8.0000, determine the matrix entries (E) in entries.

Given

  • rows(elementsofthefirstset)(nr)=19.0000rows (elements of the first set) (n_r) = 19.0000
  • columns(elementsofthesecondset)(nc)=8.0000columns (elements of the second set) (n_c) = 8.0000

Find

matrix entries (E), in entries

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for E:

    E=nrncE = n_r n_c
  3. Step 3 — List the givens: rows (elements of the first set) (n_r) = 19.0000, columns (elements of the second set) (n_c) = 8.0000.

  4. Step 4 — Substitute the given values:

    E=nrncE = n_r n_c
  5. Step 5 — Evaluate:

    E=152.0 entriesE = 152.0\ \text{entries}
  6. Step 6 — Check: returning E = 152.0 entries to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=152.0 entriesE = 152.0\ \text{entries}

Why the other options are there

  • 304.0 — kept a factor of two that cancels in the correct rearrangement.
  • 76.0000 — dropped that same factor in the other direction.
  • 167.2 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 5
Entries in a relation (adjacency) matrix — solve for rows (elements of the first set) (case 2) — Finite State Machine (5)

a finite state machine transition table stored as a Boolean matrix Given matrix entries (E) = 113.0 entries; columns (elements of the second set) (n_c) = 14.0000, determine the rows (elements of the first set) (n_r).

Given

  • matrixentries(E)=113.0entriesmatrix entries (E) = 113.0 entries
  • columns(elementsofthesecondset)(nc)=14.0000columns (elements of the second set) (n_c) = 14.0000

Find

rows (elements of the first set) (n_r)

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except n_r is given, so isolate n_r symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for n_r:

    nr=Encn_{r} = \dfrac{E}{n_c}
  3. Step 3

    Listthegivens:matrixentries(E)=113.0entries,columns(elementsofthesecondset)(nc)=14.0000List the givens: matrix entries (E) = 113.0 entries, columns (elements of the second set) (n_c) = 14.0000
  4. Step 4 — Substitute the given values:

    nr=113.0ncn_{r} = \dfrac{113.0}{n_c}
  5. Step 5 — Evaluate:

    nr=8.0714n_{r} = 8.0714
  6. Step 6 — Check: returning n_r = 8.0714 to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
nr=8.0714n_{r} = 8.0714

Why the other options are there

  • 16.1429 — kept a factor of two that cancels in the correct rearrangement.
  • 4.0357 — dropped that same factor in the other direction.
  • 8.8786 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 6
Entries in a relation (adjacency) matrix — solve for columns (elements of the second set) (case 2) — Finite State Machine (6)

a relation matrix linking pipe nodes to demand nodes Given matrix entries (E) = 139.0 entries; rows (elements of the first set) (n_r) = 17.0000, determine the columns (elements of the second set) (n_c).

Given

  • matrixentries(E)=139.0entriesmatrix entries (E) = 139.0 entries
  • rows(elementsofthefirstset)(nr)=17.0000rows (elements of the first set) (n_r) = 17.0000

Find

columns (elements of the second set) (n_c)

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except n_c is given, so isolate n_c symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for n_c:

    nc=Enrn_{c} = \dfrac{E}{n_r}
  3. Step 3

    Listthegivens:matrixentries(E)=139.0entries,rows(elementsofthefirstset)(nr)=17.0000List the givens: matrix entries (E) = 139.0 entries, rows (elements of the first set) (n_r) = 17.0000
  4. Step 4 — Substitute the given values:

    nc=139.0nrn_{c} = \dfrac{139.0}{n_r}
  5. Step 5 — Evaluate:

    nc=8.1765n_{c} = 8.1765
  6. Step 6 — Check: returning n_c = 8.1765 to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
nc=8.1765n_{c} = 8.1765

Why the other options are there

  • 16.3529 — kept a factor of two that cancels in the correct rearrangement.
  • 4.0882 — dropped that same factor in the other direction.
  • 8.9941 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 7
Entries in a relation (adjacency) matrix — solve for matrix entries (case 3) — Finite State Machine (7)

a relation matrix linking survey stations to control points Given rows (elements of the first set) (n_r) = 13.0000; columns (elements of the second set) (n_c) = 20.0000, determine the matrix entries (E) in entries.

Given

  • rows(elementsofthefirstset)(nr)=13.0000rows (elements of the first set) (n_r) = 13.0000
  • columns(elementsofthesecondset)(nc)=20.0000columns (elements of the second set) (n_c) = 20.0000

Find

matrix entries (E), in entries

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for E:

    E=nrncE = n_r n_c
  3. Step 3 — List the givens: rows (elements of the first set) (n_r) = 13.0000, columns (elements of the second set) (n_c) = 20.0000.

  4. Step 4 — Substitute the given values:

    E=nrncE = n_r n_c
  5. Step 5 — Evaluate:

    E=260.0 entriesE = 260.0\ \text{entries}
  6. Step 6 — Check: returning E = 260.0 entries to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=260.0 entriesE = 260.0\ \text{entries}

Why the other options are there

  • 520.0 — kept a factor of two that cancels in the correct rearrangement.
  • 130.0 — dropped that same factor in the other direction.
  • 286.0 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 8
Entries in a relation (adjacency) matrix — solve for rows (elements of the first set) (case 3) — Finite State Machine (8)

a finite state machine transition table stored as a Boolean matrix Given matrix entries (E) = 136.0 entries; columns (elements of the second set) (n_c) = 13.0000, determine the rows (elements of the first set) (n_r).

Given

  • matrixentries(E)=136.0entriesmatrix entries (E) = 136.0 entries
  • columns(elementsofthesecondset)(nc)=13.0000columns (elements of the second set) (n_c) = 13.0000

Find

rows (elements of the first set) (n_r)

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except n_r is given, so isolate n_r symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for n_r:

    nr=Encn_{r} = \dfrac{E}{n_c}
  3. Step 3

    Listthegivens:matrixentries(E)=136.0entries,columns(elementsofthesecondset)(nc)=13.0000List the givens: matrix entries (E) = 136.0 entries, columns (elements of the second set) (n_c) = 13.0000
  4. Step 4 — Substitute the given values:

    nr=136.0ncn_{r} = \dfrac{136.0}{n_c}
  5. Step 5 — Evaluate:

    nr=10.4615n_{r} = 10.4615
  6. Step 6 — Check: returning n_r = 10.4615 to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
nr=10.4615n_{r} = 10.4615

Why the other options are there

  • 20.9231 — kept a factor of two that cancels in the correct rearrangement.
  • 5.2308 — dropped that same factor in the other direction.
  • 11.5077 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 9
Entries in a relation (adjacency) matrix — solve for columns (elements of the second set) (case 3) — Finite State Machine (9)

a relation matrix linking pipe nodes to demand nodes Given matrix entries (E) = 34.0000 entries; rows (elements of the first set) (n_r) = 6.0000, determine the columns (elements of the second set) (n_c).

Given

  • matrixentries(E)=34.0000entriesmatrix entries (E) = 34.0000 entries
  • rows(elementsofthefirstset)(nr)=6.0000rows (elements of the first set) (n_r) = 6.0000

Find

columns (elements of the second set) (n_c)

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except n_c is given, so isolate n_c symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for n_c:

    nc=Enrn_{c} = \dfrac{E}{n_r}
  3. Step 3

    Listthegivens:matrixentries(E)=34.0000entries,rows(elementsofthefirstset)(nr)=6.0000List the givens: matrix entries (E) = 34.0000 entries, rows (elements of the first set) (n_r) = 6.0000
  4. Step 4 — Substitute the given values:

    nc=34.0000nrn_{c} = \dfrac{34.0000}{n_r}
  5. Step 5 — Evaluate:

    nc=5.6667n_{c} = 5.6667
  6. Step 6 — Check: returning n_c = 5.6667 to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
nc=5.6667n_{c} = 5.6667

Why the other options are there

  • 11.3333 — kept a factor of two that cancels in the correct rearrangement.
  • 2.8333 — dropped that same factor in the other direction.
  • 6.2333 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

Example 10
Entries in a relation (adjacency) matrix — solve for matrix entries (case 4) — Finite State Machine (10)

a relation matrix linking survey stations to control points Given rows (elements of the first set) (n_r) = 6.0000; columns (elements of the second set) (n_c) = 15.0000, determine the matrix entries (E) in entries.

Given

  • rows(elementsofthefirstset)(nr)=6.0000rows (elements of the first set) (n_r) = 6.0000
  • columns(elementsofthesecondset)(nc)=15.0000columns (elements of the second set) (n_c) = 15.0000

Find

matrix entries (E), in entries

Start with the thinking

  • The governing relation printed in this handbook section is Entries in a relation (adjacency) matrix.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • A relation between two finite sets is stored as a Boolean matrix of relation, so the storage cost is the entry count.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=nrncE = n_r n_c
  2. Step 2 — Rearrange symbolically for E:

    E=nrncE = n_r n_c
  3. Step 3 — List the givens: rows (elements of the first set) (n_r) = 6.0000, columns (elements of the second set) (n_c) = 15.0000.

  4. Step 4 — Substitute the given values:

    E=nrncE = n_r n_c
  5. Step 5 — Evaluate:

    E=90.0000 entriesE = 90.0000\ \text{entries}
  6. Step 6 — Check: returning E = 90.0000 entries to

    E=nrncE = n_r n_c

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=90.0000 entriesE = 90.0000\ \text{entries}

Why the other options are there

  • 180.0 — kept a factor of two that cancels in the correct rearrangement.
  • 45.0000 — dropped that same factor in the other direction.
  • 99.0000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Discrete Mathematics (Matrix of Relation)

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