The T-Method: One Setup for Most Real Estate Math

Most exam math — commissions, loan interest, cap rates, tax rates — is one relationship wearing different clothes: a part equals a total multiplied by a rate. The T-method is the standard way to organize it so the setup, not luck, picks the operation.

Enter any two values below and the solver fills in the third, showing the operation it used — the same move you'll make on paper on exam day.

The formula

Part = Total × Rate · Total = Part ÷ Rate · Rate = Part ÷ Total

Part
the smaller piece: commission $, annual interest $, NOI, tax due
Total
the whole: sale price, loan amount, property value, assessed value
Rate
the percentage connecting them

Try it live

Every intermediate step is shown — the goal is that on exam day you can run the same chain on paper.

T-method solver

Solve for
$

Commission, interest, tax due

$

Price, loan, value

Solved
%

Computed from the other two.

Enter the two you know. The third stays in place, dashed and in blue, so the setup you'd write on paper is the setup on screen.

The T-bar

Part

$15,000

Total

$250,000

Rate

6%

Rate = 15,000 ÷ 250,000

Cover the value you want and the T-bar shows the operation: side by side means multiply, one over the other means divide. If the rate lands above 100% or the part exceeds the total, the setup is upside down.

The method, worked in exam style

A property sells for $250,000 and the seller pays a $15,000 commission. What commission rate was charged?

  1. Identify the pieces: the commission ($15,000) is the Part; the sale price ($250,000) is the Total; the Rate is missing.
  2. Missing rate → divide the Part by the Total: 15,000 ÷ 250,000 = 0.06.
  3. Convert to a percentage: 0.06 = 6%.

Answer: 6%

The classic trap

The classic distractor divides the wrong direction — 250,000 ÷ 15,000 ≈ 16.7 — or multiplies when it should divide. If your 'rate' comes out over 100% or your 'part' is bigger than the total, the setup is upside down.

Practice problems

Work each on paper first, then open the solution. If your setup differs from the solution's first line, that — not arithmetic — is what to fix.

  1. 1. A lender charges $8,750 annual interest on a $125,000 interest-only loan. What is the interest rate?

    Show the solution
    1. Interest paid is the Part; the loan amount is the Total.
    2. Rate = Part ÷ Total = 8,750 ÷ 125,000 = 0.07.

    Answer: 7%

  2. 2. An investor wants $21,600 per year from an investment yielding 8%. How much must be invested?

    Show the solution
    1. The desired income is the Part; the yield is the Rate; the investment is the missing Total.
    2. Total = Part ÷ Rate = 21,600 ÷ 0.08 = 270,000.

    Answer: $270,000

  3. 3. A house is assessed at $180,000 and taxed at 2.5% of assessed value. What is the annual tax?

    Show the solution
    1. Assessed value is the Total; the tax rate is the Rate; tax due is the Part.
    2. Part = Total × Rate = 180,000 × 0.025 = 4,500.

    Answer: $4,500

Math is one domain — the diagnostic measures all of them

The free 24-question adaptive diagnostic finds the difficulty level where your setup breaks down — in math and every other blueprint domain — and reports a Readiness Score with a stated confidence range.

Keep going: Commission splits · Cap rate · Real Estate Math on the exam

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The T-Method for Real Estate Math · PassDeed