Threshold MLO Prep NMLS SAFE MLO Test Prep

Mortgage Math: practice questions

Module 13 of 15 · Mortgage loan origination activities (27% of the NMLS SAFE MLO Test)
Content last updated 23 September 2026

About this module

NMLS weights mortgage loan origination activities at 27% of the 115 scored questions. NMLS does not publish weights below that level, so our exam-length mix gives this module 3 of the 115, in proportion to its share of the outline topics in that area (outline section 4.D).

The full bank holds 15 questions for this module, each with a written explanation that cites its source. Below are the 8 free questions for this module, with answers.

Key sources

The law and guidance the questions in this module cite most often.

Free Mortgage Math questions

The correct finance charge on a mortgage is $6,000. Which disclosed finance charge would NOT be treated as accurate?

  1. $5,850 ✓
  2. $5,925
  3. $6,050
  4. $6,400

Why: 12 CFR 1026.18(d)(1) treats the finance charge on a mortgage as accurate if it is understated by no more than $100 or is greater than the amount required. $5,850 is understated by $150; $5,925 is within $100; $6,050 and $6,400 are overstatements. The same $100 test applies under 1026.38(o)(2) for loans with a Closing Disclosure.

Source: 12 CFR 1026.18(d)(1); 1026.38(o)(2)

According to the CFPB's ARM handbook, what is an ARM's interest rate generally never lower than?

  1. The margin ✓
  2. The index as it stood at closing
  3. The initial interest rate on the note
  4. The fully indexed rate at the first change

Why: CHARM, describing the Minimum/Maximum Interest Rate row of the AIR table: "Generally, an ARM's interest rate is never lower than the margin." The sample table with a 2.5% margin shows a 2.5% minimum.

Source: CFPB Consumer Handbook on Adjustable-Rate Mortgages (CHARM), pp. 12-13

Which of these charges on a home purchase loan is part of the finance charge? All fees are bona fide and reasonable.

  1. A bona fide title insurance premium
  2. A reasonable notary fee for the closing
  3. An appraisal fee for a pre-closing appraisal
  4. Discount points paid to the creditor ✓

Why: 12 CFR 1026.4(b)(3) lists "Points, loan fees, assumption fees, finder's fees, and similar charges" as finance charges. In a transaction secured by real property, 1026.4(c)(7) excludes bona fide and reasonable fees for title insurance, notary fees and pre-closing appraisal fees.

Source: 12 CFR 1026.4(b)(3), (c)(7)

An ARM's Adjustable Interest Rate table shows an initial rate of 3% and a maximum rate of 8%. By how many percentage points can the rate rise over the life of the loan?

  1. 2
  2. 5 ✓
  3. 8
  4. 11

Why: CHARM describes the Minimum/Maximum Interest Rate row as showing how high the rate could be over the life of the loan. Its sample AIR table shows 3% initial and 8% maximum, a lifetime rise of 8 - 3 = 5 percentage points.

Source: CFPB Consumer Handbook on Adjustable-Rate Mortgages (CHARM), pp. 12-13

A construction loan is paid out in several advances. The correct APR is 7.000% and 7.200% is disclosed. Is the APR accurate?

  1. No; every closed-end mortgage has only a 1/8 point tolerance
  2. No; APRs on mortgages must be exact to the third decimal place
  3. Yes; loans with multiple advances have a 1/4 point tolerance ✓
  4. Yes; any APR error under half a percentage point is tolerated

Why: 12 CFR 1026.22(a)(3) treats the APR in an irregular transaction as accurate within 1/4 of one percentage point, and defines irregular transactions to include those with multiple advances. 7.200% is 0.2 above, within 0.25.

Source: 12 CFR 1026.22(a)(3)

An ARM uses an index that currently stands at 2.75% and a margin of 2.25%. What is the fully indexed rate?

  1. 2.75%
  2. 4.75%
  3. 5% ✓
  4. 5.25%

Why: The CFPB's Consumer Handbook on Adjustable-Rate Mortgages (CHARM) states "Interest rate = index + margin": the margin is an extra percentage the lender adds to the index. 2.75% + 2.25% = 5%.

Source: CFPB Consumer Handbook on Adjustable-Rate Mortgages (CHARM), p. 4

A lender charges every applicant a $300 application fee, whether or not the loan is approved. How is the fee treated for Truth in Lending purposes?

  1. It is a finance charge, as the lender imposes it
  2. It is excluded from the finance charge ✓
  3. It is a finance charge only if the loan closes
  4. It is added to the amount financed at closing

Why: 12 CFR 1026.4(c)(1) excludes from the finance charge "Application fees charged to all applicants for credit, whether or not credit is actually extended."

Source: 12 CFR 1026.4(c)(1)

A 5/1 ARM has a 3% initial rate, a margin of 2.5% and a 2% limit on the first change. At the first adjustment the index is 2%. What is the new rate?

  1. 2.5%
  2. 3.0%
  3. 4.5% ✓
  4. 5.0%

Why: CHARM explains that at the first adjustment the initial rate changes to the index plus the margin, subject to the limits on interest rate changes. 2% + 2.5% = 4.5%, which is within the 2-point first-change limit (3% + 2% = 5%), so the rate becomes 4.5%. CHARM uses the same figures in its teaser-rate example.

Source: CFPB Consumer Handbook on Adjustable-Rate Mortgages (CHARM), pp. 12-13