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Mathematics
The Mathematics section of the ATI TEAS 7 tests the numerical skills nurses use daily, from calculating medication dosages to interpreting patient data. It focuses on two main areas: numbers and algebra, and measurement and data. You are allowed a basic four-function calculator, but understanding the underlying operations matters more than button-pushing. This chapter reviews arithmetic with fractions, decimals, and percentages; solving equations and proportions; converting units of measurement; and reading and interpreting data. Mastering these fundamentals lets you work accurately and quickly under time pressure.
Whole Numbers, Fractions, and Decimals
Fluency with the four operations across whole numbers, fractions, and decimals is the foundation of the entire section. Nursing calculations frequently mix these forms, so you must convert among them confidently.
Follow the order of operations
Use PEMDAS: parentheses, exponents, multiplication and division (left to right), then addition and subtraction (left to right). For 4^2 + 3 x 2, compute 16 + 6 = 22.
Find common denominators to add fractions
Convert fractions to a shared denominator before adding or subtracting. For 3/4 + 1/8, rewrite 3/4 as 6/8, then add to get 7/8.
Align decimals when adding or subtracting
Line up the decimal points and fill in zeros. For 5.6 - 2.85, write 5.60 - 2.85 to get 2.75.
Convert between fractions and decimals
Divide the numerator by the denominator to get a decimal: 1/8 = 0.125. To reverse, place the decimal over its place value and simplify: 0.75 = 75/100 = 3/4.
Ratios, Proportions, and Percentages
Ratios and proportions appear constantly in nursing, from mixing solutions to scaling doses by weight. Percentages express parts of a whole and are essential for discounts, concentrations, and statistics.
Simplify ratios by the greatest common factor
Divide both terms by their greatest common factor. The ratio 12:18 divides by 6 to become 2:3 in lowest terms.
Solve proportions by cross-multiplication
For 4/6 = x/9, cross-multiply to get 6x = 36, then divide by 6 so x = 6. This method scales recipes and doses reliably.
Convert among fractions, decimals, and percents
To make a fraction a percent, divide and multiply by 100: 3/5 = 0.6 = 60%. To take a percent of a number, multiply by its decimal form.
Calculate percent increase and decrease
Find the percent of the original amount, then add or subtract. A 25% discount on $40 is $10 off, giving a $30 sale price.
Algebra and Solving Equations
Basic algebra lets you solve for an unknown quantity, a skill used when a dosage or rate is not given directly. The key idea is keeping an equation balanced while isolating the variable.
Isolate the variable using inverse operations
Undo operations in reverse order. For 3x + 7 = 22, subtract 7 to get 3x = 15, then divide by 3 so x = 5.
Do the same operation to both sides
Whatever you do to one side of an equation you must do to the other. For y/4 = 9, multiply both sides by 4 to find y = 36.
Substitute to evaluate expressions
Replace the variable with its value and simplify. For 2(x + 3) when x = 4, compute 2(7) = 14, doing the parentheses first.
Check your answer
Substitute your solution back into the original equation to confirm it makes a true statement, catching arithmetic mistakes before moving on.
Measurement and Unit Conversion
Nurses convert between metric and standard units and compute geometric measures such as area and perimeter. Precision matters because a conversion error can change a dose or a chart.
Convert within the metric system by powers of ten
Multiply or divide by 10, 100, or 1000. Since 1 meter = 100 centimeters, 2.5 meters = 250 centimeters.
Use area and perimeter formulas
Area of a rectangle is length times width; perimeter of a square is four times a side. A 7-inch square has a perimeter of 28 inches.
Track units through every step
Write the units beside each number so they cancel correctly. Reporting area in square units and volume in cubic units prevents mismatched answers.
Round appropriately
Identify the target place value, then look at the digit to its right: 5 or more rounds up. Rounding 3,847 to the nearest hundred gives 3,800.
Data, Statistics, and Graphs
Interpreting data means calculating averages, reading charts, and drawing conclusions from tables. Nurses use these skills to track vital signs, intake and output, and trends over time.
Calculate the mean
Add all values and divide by the count. If five scores average 82, their sum is 82 x 5 = 410, which you can rearrange to find a missing value.
Understand mean, median, and mode
The mean is the average, the median is the middle value in order, and the mode is the most frequent value. Choose the measure that fits the question.
Read charts and tables carefully
Check titles, axis labels, and units before interpreting a graph. Note whether values are rising, falling, or peaking to answer trend questions.
Compute totals and parts of a whole
To find a percentage of a group, divide the part by the total: 12 boys out of 30 students is 12/30 = 40%.
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