The ratio of the number of girls to boys in a school of 3240 students is 35:37. How many more girls should be admitted to make the ratio 1:1?

1. A

   90

2. B

   100

3. C

   70

4. D

   80

Appeared in: HPSSC - 2015

Explanation

• The total number of parts in the ratio 35:37 is 72 (35 + 37).
• With a total of 3240 students, each part of the ratio represents 45 students (3240 / 72).
• The current number of girls is 1575 (35 x 45) and boys is 1665 (37 x 45).
• To achieve a 1:1 ratio, the number of girls must equal the number of boys (1665).
• The difference between the number of boys and the current number of girls is 90 (1665 - 1575), which is the number of girls that need to be admitted.

Why Other Options Were Wrong

• Option B: This is an incorrect calculation. It may arise from rounding numbers during intermediate steps or a simple arithmetic error.
• Option C: This is an incorrect calculation. It may arise from rounding numbers during intermediate steps or a simple arithmetic error.
• Option D: This is an incorrect calculation. It may arise from rounding numbers during intermediate steps or a simple arithmetic error.

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Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Solving problems involving ratios and proportions as background academic context rather than a clinical decision trigger.
• While not a clinical question, understanding ratios is crucial in healthcare for tasks like calculating drug dosages, interpreting lab value ratios (e.g., albumin/globulin ratio), and managing staff-to-patient ratios for safe care.
• For example, if a medication needs to be mixed in a 1:100 solution, an error in calculating the ratio could lead to a significant medication error, harming the patient.
• What if the question asked to make the ratio 36:37? You would calculate the new target number of girls based on the new ratio relative to the constant number of boys and find the difference from the current number of girls.

How to Approach the Question

• First, identify the given information: total students (3240), initial ratio (35:37), and target ratio (1:1).
• Calculate the total number of parts in the initial ratio by adding the parts for girls and boys.
• Determine the value of a single 'part' by dividing the total number of students by the total number of parts.
• Calculate the current number of girls and boys by multiplying their respective ratio parts by the value of a single part.
• To find the number of girls to add for a 1:1 ratio, find the difference between the number of boys and the current number of girls. The number of boys remains constant as only girls are being added.

Concept Tested & Keywords

• Concept Tested: Solving problems involving ratios and proportions.
• Stem keywords: ratio, girls, boys, students, 3240, 35:37
• Lead-in keywords: How many more

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Q03HJvFjp_mfeOpZv4IBG1

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