If "P" denotes "multiplied by", "R" denotes "subtracted from", "S" denotes "added to" and "Q" denotes "divided by", then which of the following equation is true ?

1. A

   18 R 60 Q 15 S 2 = 8

2. B

   15 S 16 Q 2 P 4 = 47

3. C

   3 P 5 R 18 Q 3 = 6

4. D

   15 S 28 Q 4 P 2 = 27

Appeared in: Haryana CHO -2023

Explanation

• The question requires substituting the given letters with their corresponding mathematical operators and then evaluating the expression.
• The correct equation is the one that remains mathematically true after substitution and applying the BODMAS rule (Brackets, Orders, Division, Multiplication, Addition, Subtraction).
• Evaluating the expression '15 S 16 Q 2 P 4' gives: 15 + 16 ÷ 2 × 4.
• Following BODMAS, division is performed first (16 ÷ 2 = 8), followed by multiplication (8 × 4 = 32), and finally addition (15 + 32 = 47).
• The result, 47, matches the right side of the equation, making it the true statement.

Why Other Options Were Wrong

• Option A: After substitution, the expression is 18 - 60 ÷ 15 + 2. Following BODMAS, this evaluates to 18 - 4 + 2 = 16, which is not equal to 8.
• Option C: After substitution, the expression is 3 × 5 - 18 ÷ 3. Following BODMAS, this evaluates to 15 - 6 = 9, which is not equal to 6.
• Option D: After substitution, the expression is 15 + 28 ÷ 4 × 2. Following BODMAS, this evaluates to 15 + 7 × 2 = 15 + 14 = 29, which is not equal to 27.

Related Visual

Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Solving mathematical expressions using symbol substitution and the BODMAS rule as background academic context rather than a clinical decision trigger.
• This type of question assesses logical and analytical reasoning, a crucial skill for nurses in making quick, accurate decisions during patient care, especially in medication calculation.
• While not directly clinical, the ability to follow a set order of operations (like BODMAS) is analogous to following a strict protocol or algorithm in a medical emergency, ensuring no steps are missed and patient safety is maintained.
• What if the BODMAS rule was ignored? If addition was performed before division in the correct option (15 + 16 ÷ 2 × 4), the result would be (31 ÷ 2) × 4 = 15.5 × 4 = 62, which is incorrect. This highlights the critical importance of procedural accuracy in nursing tasks like dose calculation.

How to Approach the Question

• First, carefully read the question and create a clear key for what each symbol represents (e.g., P = ×, R = -, S = +, Q = ÷).
• Take each option one by one and substitute the symbols with their corresponding mathematical operators.
• Apply the BODMAS rule to solve the resulting mathematical expression. BODMAS stands for Brackets, Orders, Division, Multiplication, Addition, and Subtraction.
• Remember that Division and Multiplication have equal priority and are solved from left to right as they appear in the equation.
• Similarly, Addition and Subtraction have equal priority and are solved from left to right.
• Compare the result of your calculation with the number given on the right side of the equals sign. The option where the left side equals the right side is the correct answer.

Concept Tested & Keywords

• Concept Tested: Solving mathematical expressions using symbol substitution and the BODMAS rule.
• Stem keywords: P denotes multiplied by, R denotes subtracted from, S denotes added to, Q denotes divided by, equation is true
• Lead-in keywords: which of the following

Question ID

QefACaSLN0E5GfzL3J1Cly

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