Preparing for the HESI A2 can feel overwhelming, especially when you are unsure which math skills deserve the most attention. The good news is that you do not need to master every advanced mathematical concept to perform well. Instead, focusing on the fundamental topics commonly tested in the HESI A2 Math section can help you build confidence and improve your accuracy.

The most important areas to review include fractions, decimals, ratios, percentages, basic algebra, and measurement conversions. These topics form the foundation of many of the problems you may encounter on the exam.

Here is a closer look at each area and the skills you should practice before test day.

1. Fractions

Fractions represent parts of a whole and are one of the most important concepts to understand for the HESI A2 Math section. You should be comfortable working with proper fractions, improper fractions, mixed numbers, equivalent fractions, and fractions with different denominators.

Adding and subtracting fractions

When fractions have the same denominator, you can add or subtract their numerators while keeping the denominator unchanged.

For example:

1/4 + 1/4 = 2/4 = 1/2

When the denominators are different, you first need to find a common denominator.

For example:

1/2 + 1/3

The common denominator is 6:

3/6 + 2/6 = 5/6

Mixed numbers should generally be converted into improper fractions before performing more complicated calculations.

Multiplying and dividing fractions

Multiplication is relatively straightforward. Multiply the numerators together and then multiply the denominators.

1/2 × 1/4 = 1/8

For division, use the reciprocal of the second fraction and then multiply.

1/4 ÷ 1/2

becomes:

1/4 × 2/1 = 2/4 = 1/2

Practice converting between mixed numbers and improper fractions as well as simplifying your final answers. These skills can save valuable time during the exam.

2. Decimals

Decimals are another essential part of HESI A2 mathematics. You should know how decimal place values work and be able to move between decimals and fractions.

Consider the number 53.264. Its digits represent:

• 5 tens

• 3 ones

• 2 tenths

• 6 hundredths

• 4 thousandths

Understanding place value makes it easier to perform calculations and convert decimals into other forms.

Converting decimals to fractions

To convert a decimal into a fraction, identify the place value of the final digit and use the corresponding power of 10 as the denominator.

For example:

1.25 = 125/100

This fraction can then be simplified to:

5/4

You should also be comfortable converting fractions into decimals. For example:

4/5 = 8/10 = 0.8

Being able to move quickly between fractions and decimals is particularly useful when solving multi-step problems.

3. Ratios and Proportions

Ratios compare two quantities. They can be written using a colon, such as 2:1, or expressed as a fraction.

For example, if one student has 20 pencils and another has 10, their quantities can be expressed as:

20:10 = 2:1

Before comparing quantities, make sure they use the same units. If one measurement is given in feet and another in yards, convert them to the same unit first.

Solving proportions

A proportion occurs when two ratios are equal. For example:

a/b = c/d

When one value is unknown, cross-multiplication can often be used to solve the problem.

Suppose a patient loses 1.5 pounds every three days. If the same rate continues, you could set up:

1.5/3 = x/10

Cross-multiplying gives:

3x = 15

Therefore:

x = 5

Questions involving ratios and proportions often appear in practical situations, so practice identifying the quantities being compared before setting up your equation.

4. Percentages

Percentages describe quantities in relation to 100. Because they are essentially ratios with 100 as the denominator, they can often be solved using proportions.

For example:

40% = 40/100 = 0.40

You should be able to calculate a percentage of a number, convert percentages into decimals or fractions, and solve problems involving percentage increases or decreases.

Applying percentages to real-world problems

Percentage questions can involve population statistics, discounts, test scores, concentrations, or healthcare-related calculations.

For example, if you need to find 15% of 200:

15/100 × 200 = 30

The ability to recognize what a percentage represents is just as important as knowing how to perform the calculation.

When studying, practice both straightforward percentage questions and word problems. This will help you become comfortable translating written information into mathematical equations.

5. Basic Algebra

You do not need advanced algebra to prepare for the HESI A2, but you should understand how to solve simple equations containing an unknown variable.

The goal is usually to isolate the variable on one side of the equation while maintaining equality.

For example:

3(x - 5) = 3

First, divide both sides by 3:

x - 5 = 1

Then add 5 to both sides:

x = 6

One of the most important algebra rules is that whatever operation you perform on one side of an equation must also be performed on the other side.

Use the answer choices to your advantage

Because the HESI A2 uses multiple-choice questions, the answer options can sometimes help you check your work. If you are unsure about your equation, substitute the available choices into the original problem and determine which one makes the equation true.

This approach can be especially useful when you are short on time.

6. Measurement and Metric Conversions

Measurement conversions are particularly important because healthcare professionals regularly work with different units of measurement.

You should be familiar with common metric units for length, mass, and volume, including:

• Meter (m)

• Centimeter (cm)

• Millimeter (mm)

• Kilogram (kg)

• Gram (g)

• Milligram (mg)

• Liter (L)

• Milliliter (mL)

The metric system is based on powers of 10, which makes conversions easier once you understand how the units relate to one another.

For example:

1 gram = 1,000 milligrams

Therefore:

13.86 grams = 13,860 milligrams

You may also encounter questions requiring conversions between metric and U.S. customary units. These problems require careful attention to the conversion factor provided in the question.

Always check whether the question asks you to move from a larger unit to a smaller one or the other way around. A misplaced decimal point can turn an otherwise correct calculation into a wrong answer.

How to Prepare for the HESI A2 Math Section

Knowing the topics is only the first step. Your preparation should also include regular practice.

Start by reviewing the mathematical concepts you find most difficult. If fractions are challenging, spend additional time practicing operations with fractions before moving on to more advanced topics.

You should also practice word problems. HESI A2 questions may require you to read a situation, identify the relevant information, choose the appropriate mathematical operation, and calculate the answer.

Another useful strategy is to practice under timed conditions. This allows you to become familiar with solving problems efficiently without spending too much time on a single question.

Most importantly, pay attention to your mistakes. Rather than simply memorizing the correct answer, determine why your original approach was incorrect. This helps you recognize similar problems when they appear again.

Final Thoughts

A strong foundation in basic mathematics can make the HESI A2 Math section much more manageable. Focus your preparation on fractions, decimals, ratios, percentages, basic algebra, and measurement conversions, then reinforce those skills through repeated practice.

Do not wait until the last few days before the exam to review these concepts. Consistent practice gives you more opportunities to identify weak areas, improve your calculation speed, and become more confident with different question types.