Mental Math and Fermi Final Review
Mental math and Fermi final review for quant interviews, covering arithmetic checks, estimation frameworks, timed drills, and error-log repair.
Candidates finishing a mental math and estimation prep block.
Review arithmetic mechanics
Check fractions, percentages, rough multiplication, division, square roots, and EV-weighted averages. Focus on calculation types that actually appear in your misses.
Review Fermi structure
For estimation prompts, state the target, build a factor tree, choose ranges, multiply cleanly, and sanity-check the final scale.
Concrete final drill
Run ten arithmetic questions, one EV mental math prompt, and one Fermi estimate. Then review every miss before doing another timed set.
Use the error log
Pick the top two recurring errors and assign repair drills. Final review should reduce repeated misses, not just reread old notes.
Common mistakes
Candidates often use final review as passive reading. Mental math and estimation need live reps because pressure changes error patterns.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.