Decimal to Fraction Quant Interview Guide
Decimal to fraction quant interview guide for converting decimals, percentages, and fractions quickly during probability and EV prompts.
Candidates who lose time moving between decimal and fraction forms.
Choose the useful representation
Fractions are often cleaner for exact probability. Decimals are often clearer for prices, percentages, and comparison. Good mental math switches forms deliberately.
Know common pairs
Memorize 0.125 as 1/8, 0.2 as 1/5, 0.25 as 1/4, 0.375 as 3/8, 0.625 as 5/8, and 0.75 as 3/4. These appear repeatedly in interview arithmetic.
Concrete example
If a quote implies 0.625 probability, translate it to 5/8 when comparing with a dice or card fraction. Exact comparison can be easier than decimal subtraction.
Use complements
A decimal like 0.875 is easier as 1 - 0.125, which is 7/8. Complements help when probabilities are close to zero or one.
Common mistakes
Candidates sometimes force exact conversion when an approximation is enough. State whether you need an exact fraction or just a comparison-quality estimate.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.