NEX Mathematics 2 — Questions and Answers

Question 1: What is 3/8 + 5/12?

8/20
19/24 (Correct answer)
15/32
1/3

Correct answer: 19/24

Find the LCD (24): 3/8 = 9/24, 5/12 = 10/24. Sum: 9/24 + 10/24 = 19/24.

Adding fractions requires a common denominator. The least common denominator (LCD) of 8 and 12 is 24. Convert each fraction: 3/8 × 3/3 = 9/24 and 5/12 × 2/2 = 10/24. Add the numerators: 9 + 10 = 19. The result is 19/24, which is already in simplest form since 19 is prime and not a factor of 24. Finding the LCD: list multiples of 8 (8, 16, 24, 32...) and 12 (12, 24, 36...), and 24 is the first common multiple. Alternatively, factor both: 8 = 2³ and 12 = 2² × 3, so LCD = 2³ × 3 = 24. Fraction operations are essential for nursing calculations involving medication dosages, IV rates, and solution preparations.

Question 2: A nurse works 36 hours per week. If she receives a 15% pay increase on her hourly rate of $28, what is her new weekly pay?

$1,008.00
$1,058.40
$1,159.20 (Correct answer)
$1,188.00

Correct answer: $1,159.20

New hourly rate: $28 × 1.15 = $32.20. New weekly pay: $32.20 × 36 = $1,159.20.

Percentage increase calculations: multiply the original amount by (1 + percentage as a decimal). New hourly rate: $28 × 1.15 = $32.20. Alternatively, find the increase: $28 × 0.15 = $4.20, then add: $28 + $4.20 = $32.20. Weekly pay: $32.20 × 36 hours = $1,159.20. This type of percentage calculation appears frequently on nursing entrance exams and is also practical for understanding pay scales, medication concentration changes, and patient vital sign changes expressed as percentages. Common errors include calculating 15% of the new amount instead of the original, or forgetting to add the increase to the original amount.

Question 3: Simplify: 4² × 3 - 2(5 + 3)

16
32 (Correct answer)
40
64

Correct answer: 32

Following order of operations (PEMDAS): 4² = 16, parentheses: 5+3 = 8, then 16 × 3 = 48, and 2 × 8 = 16. Finally: 48 - 16 = 32.

Order of operations (PEMDAS/BODMAS): Parentheses/Brackets, Exponents/Orders, Multiplication and Division (left to right), Addition and Subtraction (left to right). Step by step: (1) Parentheses: (5 + 3) = 8. (2) Exponents: 4² = 16. (3) Multiplication (left to right): 16 × 3 = 48 and 2 × 8 = 16. (4) Subtraction: 48 - 16 = 32. A common error is performing operations left to right without following PEMDAS, which would give incorrect results. In nursing mathematics, order of operations is critical when calculating complex dosages involving multiple conversion steps. For example, calculating an adjusted body weight for obese patients involves multiple operations that must be performed in the correct order.

Question 4: Convert 2.75 to a fraction in lowest terms.

2 3/4
2 7/10
11/4
Both A and C (Correct answer)

Correct answer: Both A and C

2.75 = 2 + 0.75 = 2 + 75/100 = 2 + 3/4 = 2 3/4, which equals 11/4 as an improper fraction. Both A and C are correct representations.

Converting 2.75 to a fraction: The whole number is 2, and the decimal 0.75 = 75/100. Simplify 75/100 by dividing both by 25: 75 ÷ 25 = 3, 100 ÷ 25 = 4, giving 3/4. As a mixed number: 2 3/4. As an improper fraction: 2 × 4 + 3 = 11, so 11/4. Both representations are mathematically equivalent and correct. In nursing, converting between decimals and fractions is essential: medication orders may use either form, and nurses must be comfortable converting between them. For example, a 0.25 mg tablet is the same as a 1/4 mg tablet, and understanding this equivalence prevents medication errors.

Question 5: If a medication vial costs $12.50 and the hospital uses an average of 8 vials per day, what is the monthly cost for 30 days?

$2,500
$3,000 (Correct answer)
$3,750
$4,000

Correct answer: $3,000

Daily cost: $12.50 × 8 = $100. Monthly cost: $100 × 30 = $3,000.

This is a multi-step multiplication problem: Daily cost = price per vial × vials per day = $12.50 × 8 = $100.00 per day. Monthly cost = daily cost × days = $100.00 × 30 = $3,000.00. Tip for multiplying by $12.50: $12.50 × 8 = $12 × 8 + $0.50 × 8 = $96 + $4 = $100. Understanding cost calculations is increasingly important in healthcare as nurses participate in resource management, supply chain decisions, and cost-effective care planning. These calculations also appear on nursing entrance exams as practical math applications.

Question 6: What is the mean of the following patient temperatures: 98.6, 99.2, 100.4, 98.8, 101.0?

99.4°F
99.6°F (Correct answer)
99.8°F
100.0°F

Correct answer: 99.6°F

Mean = sum of all values / number of values = (98.6 + 99.2 + 100.4 + 98.8 + 101.0) / 5 = 498.0 / 5 = 99.6°F.

The mean (average) is calculated by summing all values and dividing by the number of values. Sum: 98.6 + 99.2 + 100.4 + 98.8 + 101.0 = 498.0. Count: 5 readings. Mean: 498.0 ÷ 5 = 99.6°F. In healthcare, understanding measures of central tendency (mean, median, mode) is important for interpreting patient data trends, research results, and quality metrics. The mean temperature of 99.6°F is slightly elevated above normal (98.6°F), suggesting a low-grade fever trend. For skewed data, the median (middle value when ordered: 99.2) may be more representative. Range (101.0 - 98.6 = 2.4°F) shows the spread of values.

NEX Mathematics 2

What is 3/8 + 5/12?