Math Concepts for HESI Exam

Overview

This lecture provides a comprehensive review of basic math concepts needed for the HESI exam and other pre-nursing entrance tests, covering key definitions, calculations, conversions, and problem-solving strategies.

Exam Basics

• HESI math section has 55 questions in 50 minutes; calculator and scratch paper provided.
• Topics include fractions, decimals, measurements, percentages, conversions, ratios, proportions, algebra, and military time.

Math Vocabulary & Concepts

• Know terms like exponent, expression, factor, fraction bar, numerator, denominator, constant, dividend, divisor, remainder, variable, sum.
• Understanding vocabulary ensures you interpret questions correctly.

Basic Calculations & Strategies

• Use calculator for arithmetic; check decimal placements.
• For division/multiplication, remember to align numbers properly (especially decimals).

Roman Numerals

• I=1, V=5, X=10, L=50, C=100, D=500, M=1,000.
• Smaller numeral before larger = subtract; otherwise, add.
• Bar above numeral multiplies its value by 1,000 (e.g., V̅ = 5,000).

Metric System & Conversions

• 1 kilometer = 1,000 meters, 1 meter = 100 centimeters, 1 centimeter = 10 millimeters, 2.54 cm = 1 inch.
• 1 gallon = 4 quarts = 8 pints = 16 cups = 128 oz.
• 1 cup = 8 oz; 1 oz = 30 mL; 1 lb = 16 oz; 2.2 lbs = 1 kg.
• King Henry Died By Drinking Chocolate Milk mnemonic for metric prefixes.
• Move the decimal right or left based on converting between units.

Fractions

• Adding/subtracting: make denominators the same (least common denominator).
• Multiplying: multiply straight across.
• Dividing: flip (reciprocal) the second fraction and multiply.
• Reduce answers to simplest form.

Decimals & Percents

• Divide numerator by denominator for fraction to decimal; long division may be needed.
• To convert decimal to percent, move decimal two places right.
• To convert fraction to percent: (fraction × 100).

Ratios & Proportions

• Write ratios as a:b or a/b.
• For proportions, cross-multiply and solve for the unknown.

Word Problems

• Identify keywords ("out of," "of," "what number") to set up equations.
• Use proportions for percent and comparison problems.

Algebra Basics

• Order of operations: Parentheses, Exponents, Multiply/Divide, Add/Subtract (PEMDAS).
• Multiplication/division of same base: add/subtract exponents.
• Isolate variables by inverse operations.

Military Time

• AM: add leading zeroes (e.g., 0600 = 6:00 AM).
• PM: subtract 12 from hour (e.g., 2100 = 9:00 PM).
• 1200 = noon, 0000/2400 = midnight.

Key Terms & Definitions

• Exponent — Number indicating repeated multiplication of a base.
• Expression — Mathematical phrase with constants and variables.
• Factor — A number that divides another number evenly.
• Improper Fraction — Numerator greater than or equal to denominator.
• LCD (Least Common Denominator) — Smallest common multiple of denominators.
• Dividend — Number being divided.
• Divisor — Number dividing another number.
• Remainder — Amount left after division.
• Variable — Letter representing an unknown.
• Ratio — Comparison between two numbers.
• Proportion — Equation stating two ratios are equal.

Action Items / Next Steps

• Memorize key conversions and metric prefixes.
• Practice fraction, decimal, and percent conversions.
• Complete practice problems on ratios, proportions, and basic algebra.
• Review order of operations and military time conversions.
• Prepare scratch paper and calculator for practice tests.