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Infinix Calculators

Our Authors & Contributors

Meet the writers, engineers, and financial analysts behind our articles, cost studies, and calculation guides.

David Miller, CPA

David Miller, CPA

Lead Financial Analyst & Tax Technology Editor

CPA, M.S. Finance (NYU Stern)

David is a Certified Public Accountant (CPA) with over 14 years of corporate tax, loan amortization modeling, and merchant processing cost accounting experience.

Areas of Focus:
Loan Amortization & BNPL APR ModelingPayment Processing Interchange & Gross-Up MathUS Multi-State Sales Tax (Origin vs Destination)
Elena Rostova, P.E.

Elena Rostova, P.E.

Senior Construction Estimator & Materials Engineer

P.E., M.S. Civil Engineering (Georgia Tech)

Elena is a licensed Professional Engineer (P.E.) specializing in structural volume estimation, soil compaction physics, and bulk materials logistics.

Areas of Focus:
Topsoil & Aggregates Volumetric CalculationsSoil Compaction & Settling Margins (10-15% Buffers)Concrete Slab, Footing & Bag Estimations
Dr. Marcus Vance, Ph.D.

Dr. Marcus Vance, Ph.D.

Lead Mathematician & Psychometric Systems Editor

Ph.D. Applied Mathematics (MIT)

Dr. Vance is a research mathematician and psychometric modeler specializing in standardized test scoring distributions, inverse trigonometry, and algebraic weighted averages.

Areas of Focus:
Psychometric Equating & LSAT Scoring CurvesWeighted Star Rating Math (Google Review Calculus)Inverse Trigonometric Algorithms & Radians
Sarah Jenkins, MS, OTR/L

Sarah Jenkins, MS, OTR/L

Clinical Operations Specialist & Productivity Lead

MS, OTR/L, Healthcare Systems Management

Sarah is a healthcare operations consultant with 11 years of experience optimizing Skilled Nursing Facility (SNF) clinical productivity metrics and time allocation.

Areas of Focus:
SNF Clinical Productivity BenchmarksDirect Care vs Non-Billable Time CalculationsLunch Break & Documentation Time Deductions