A student was asked to divide a number by 5 and then add 15 to the quotient. However, he first added 15 to the number and then divided it by 5, obtaining 148 as the answer. What should be the correct answer?

1. A

   160

2. B

   140

3. C

   180

4. D

   190

Appeared in: Haryana CHO - 2022

Explanation

• The problem requires a two-step solution: first find the original number, then calculate the correct answer.
• To find the original number, reverse the student's incorrect steps. The equation is (Number + 15) / 5 = 148. Solving this gives the original number as 725.
• The correct procedure is to divide the number by 5 and then add 15.
• Applying the correct steps to the original number: (725 / 5) + 15 = 145 + 15 = 160.

Why Other Options Were Wrong

• Option B: This value would result from a calculation error after correctly finding the intermediate quotient of 145 (i.e., 725 / 5). For instance, subtracting 5 instead of adding 15.
• Option C: This is an incorrect value likely resulting from a miscalculation at some stage, either when finding the original number or when calculating the final correct answer.
• Option D: This is another incorrect value that does not follow from the correct application of the arithmetic rules described in the problem.

Related Visual

Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Solving a word problem involving arithmetic operations and order of operations as background academic context rather than a clinical decision trigger.
• While this is a general mathematics question, the underlying principle of following a precise order of operations is a critical safety skill in nursing.
• Accurate calculation is fundamental for medication administration. An error in the sequence of steps, similar to the one in the problem, could lead to a dangerous dosing error.
• For example, when reconstituting a powdered drug, a nurse must follow specific steps in order: add a precise amount of diluent, mix, and then draw up the correct volume. Reversing these steps would make correct administration impossible.

How to Approach the Question

• First, carefully read the problem to distinguish between the 'correct' procedure and the 'incorrect' one that was performed.
• Let the unknown original number be represented by a variable, such as 'x'.
• Formulate a mathematical equation based on the incorrect procedure that was performed and its result: (x + 15) / 5 = 148.
• Solve this equation for 'x' by applying inverse operations. This will give you the original number.
• Now, use the original number ('x') and apply the 'correct' procedure as described in the problem: (x / 5) + 15.
• Calculate the final value, which will be the correct answer, and match it with the given options.

Concept Tested & Keywords

• Concept Tested: Solving a word problem involving arithmetic operations and order of operations.
• Stem keywords: divide a number by 5, add 15, first added 15, divided it by 5, obtaining 148
• Lead-in keywords: What should be the correct answer?

Question ID

QepOw5m63YJJHos_UQRuDg

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