Breakeven Analysis
Engineering Economics · FE Reference Handbook section
Handbook notes for this section
Definitions and conditions exactly as the handbook states them.
- By altering the value of any one of the variables in a situation, holding all of the other values constant, it is possible to find a
- value for that variable that makes the two alternatives equally economical. This value is the breakeven point.
- Breakeven analysis is used to describe the percentage of capacity of operation for a manufacturing plant at which income will
- The payback period is the period of time required for the profit or other benefits of an investment to equal the cost of the
Core formulas for this FE topic
Definitions, applicability, units, assumptions and worked examples for each relation.
This section is conceptual; there are no equations to memorise.
Worked exam-style examples
The four ways this section is written on the real exam — thoughts first, then equations, then substitution.
A precast plant has $41,000 fixed annual cost, $25.50 variable cost per unit, and sells units at $33.00. What annual output breaks even?
Given
Fixed = $41,000
v = $25.50/unit
p = $33.00/unit
Find
Break-even quantity Q
Start with the thinking
- Break-even sets total revenue equal to total cost.
- The contribution margin is p − v.
Step-by-step solution
Balance
Rearrange
Contribution margin — p − v = $33.00 − $25.50 = $7.50/unit
Substituting — Q = $41,000/$7.50 = 5,467 units/yr
Q ≈ 5,467 units per year
Why the other options are there
- 1,242 units (variable cost ignored)
- 1,608 units (price ignored)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A contractor invests $119,000 in equipment that returns $25,000 per year for 5 years with no salvage. Determine the rate of return, and estimate the after-tax return at a 35% tax rate on the net income.
Given
P = $119,000
A = $25,000/yr
Find
Before-tax rate of return and an after-tax estimate
Start with the thinking
- The rate of return is the interest rate that makes present worth zero — solved by trial or by the calculator's IRR.
- A quick after-tax screen scales the annual return by (1 − tax rate) and re-solves.
Step-by-step solution
Formula
Set up
Solve for i
After-tax cash flow — A_at = A(1 − t) = $25,000(1 − 0.35) = $16,250
After-tax (P/A) required — 7.3231
Solve again — i_at ≈ 0.01%
Before-tax ROR ≈ 1.66% per year
Why the other options are there
- 5.0% (simple total return)
- 21.0% (ignored the time value of money)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A precast plant has $119,000 fixed annual cost, $10.00 variable cost per unit, and sells units at $23.00. What annual output breaks even?
Given
Fixed = $119,000
v = $10.00/unit
p = $23.00/unit
Find
Break-even quantity Q
Start with the thinking
- Break-even sets total revenue equal to total cost.
- The contribution margin is p − v.
Step-by-step solution
Balance
Rearrange
Contribution margin — p − v = $23.00 − $10.00 = $13.00/unit
Substituting — Q = $119,000/$13.00 = 9,154 units/yr
Q ≈ 9,154 units per year
Why the other options are there
- 5,174 units (variable cost ignored)
- 11,900 units (price ignored)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A contractor invests $85,000 in equipment that returns $18,000 per year for 8 years with no salvage. Determine the rate of return, and estimate the after-tax return at a 27% tax rate on the net income.
Given
P = $85,000
A = $18,000/yr
Find
Before-tax rate of return and an after-tax estimate
Start with the thinking
- The rate of return is the interest rate that makes present worth zero — solved by trial or by the calculator's IRR.
- A quick after-tax screen scales the annual return by (1 − tax rate) and re-solves.
Step-by-step solution
Formula
Set up
Solve for i
After-tax cash flow — A_at = A(1 − t) = $18,000(1 − 0.27) = $13,140
After-tax (P/A) required — 6.4688
Solve again — i_at ≈ 4.98%
Before-tax ROR ≈ 13.47% per year
Why the other options are there
- 69.4% (simple total return)
- 21.2% (ignored the time value of money)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A precast plant has $90,000 fixed annual cost, $17.00 variable cost per unit, and sells units at $32.50. What annual output breaks even?
Given
Fixed = $90,000
v = $17.00/unit
p = $32.50/unit
Find
Break-even quantity Q
Start with the thinking
- Break-even sets total revenue equal to total cost.
- The contribution margin is p − v.
Step-by-step solution
Balance
Rearrange
Contribution margin — p − v = $32.50 − $17.00 = $15.50/unit
Substituting — Q = $90,000/$15.50 = 5,806 units/yr
Q ≈ 5,806 units per year
Why the other options are there
- 2,769 units (variable cost ignored)
- 5,294 units (price ignored)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A contractor invests $106,000 in equipment that returns $22,000 per year for 10 years with no salvage. Determine the rate of return, and estimate the after-tax return at a 32% tax rate on the net income.
Given
P = $106,000
A = $22,000/yr
Find
Before-tax rate of return and an after-tax estimate
Start with the thinking
- The rate of return is the interest rate that makes present worth zero — solved by trial or by the calculator's IRR.
- A quick after-tax screen scales the annual return by (1 − tax rate) and re-solves.
Step-by-step solution
Formula
Set up
Solve for i
After-tax cash flow — A_at = A(1 − t) = $22,000(1 − 0.32) = $14,960
After-tax (P/A) required — 7.0856
Solve again — i_at ≈ 6.81%
Before-tax ROR ≈ 16.08% per year
Why the other options are there
- 107.5% (simple total return)
- 20.8% (ignored the time value of money)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A precast plant has $135,000 fixed annual cost, $9.00 variable cost per unit, and sells units at $20.00. What annual output breaks even?
Given
Fixed = $135,000
v = $9.00/unit
p = $20.00/unit
Find
Break-even quantity Q
Start with the thinking
- Break-even sets total revenue equal to total cost.
- The contribution margin is p − v.
Step-by-step solution
Balance
Rearrange
Contribution margin — p − v = $20.00 − $9.00 = $11.00/unit
Substituting — Q = $135,000/$11.00 = 12,273 units/yr
Q ≈ 12,273 units per year
Why the other options are there
- 6,750 units (variable cost ignored)
- 15,000 units (price ignored)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A contractor invests $135,000 in equipment that returns $33,000 per year for 10 years with no salvage. Determine the rate of return, and estimate the after-tax return at a 31% tax rate on the net income.
Given
P = $135,000
A = $33,000/yr
Find
Before-tax rate of return and an after-tax estimate
Start with the thinking
- The rate of return is the interest rate that makes present worth zero — solved by trial or by the calculator's IRR.
- A quick after-tax screen scales the annual return by (1 − tax rate) and re-solves.
Step-by-step solution
Formula
Set up
Solve for i
After-tax cash flow — A_at = A(1 − t) = $33,000(1 − 0.31) = $22,770
After-tax (P/A) required — 5.9289
Solve again — i_at ≈ 10.84%
Before-tax ROR ≈ 20.73% per year
Why the other options are there
- 144.4% (simple total return)
- 24.4% (ignored the time value of money)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A precast plant has $158,000 fixed annual cost, $24.50 variable cost per unit, and sells units at $43.00. What annual output breaks even?
Given
Fixed = $158,000
v = $24.50/unit
p = $43.00/unit
Find
Break-even quantity Q
Start with the thinking
- Break-even sets total revenue equal to total cost.
- The contribution margin is p − v.
Step-by-step solution
Balance
Rearrange
Contribution margin — p − v = $43.00 − $24.50 = $18.50/unit
Substituting — Q = $158,000/$18.50 = 8,541 units/yr
Q ≈ 8,541 units per year
Why the other options are there
- 3,674 units (variable cost ignored)
- 6,449 units (price ignored)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis
A contractor invests $200,000 in equipment that returns $33,000 per year for 8 years with no salvage. Determine the rate of return, and estimate the after-tax return at a 25% tax rate on the net income.
Given
P = $200,000
A = $33,000/yr
Find
Before-tax rate of return and an after-tax estimate
Start with the thinking
- The rate of return is the interest rate that makes present worth zero — solved by trial or by the calculator's IRR.
- A quick after-tax screen scales the annual return by (1 − tax rate) and re-solves.
Step-by-step solution
Formula
Set up
Solve for i
After-tax cash flow — A_at = A(1 − t) = $33,000(1 − 0.25) = $24,750
After-tax (P/A) required — 8.0808
Solve again — i_at ≈ 0.01%
Before-tax ROR ≈ 6.62% per year
Why the other options are there
- 32.0% (simple total return)
- 16.5% (ignored the time value of money)
Reference: FE Reference Handbook — Engineering Economics → Breakeven Analysis