Out of 120 pupils in a class, 45 attained a B grade. What percentage achieved a B grade?
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Answer: C. 37.5%
Explanation
Forty five students attained a B grade out of a total class population of one hundred twenty. Dividing forty five by one hundred twenty gives the decimal fraction equivalent of zero point three seven five. Multiplying by one hundred converts the decimal fraction into the exact percentage of thirty seven point five. Percentages express proportions relative to a total baseline population standardized at one hundred units. Grade distribution analysis relies on converting raw student counts into standard percentage representations. Division of subset counts by total counts establishes precise statistical performance metrics.
Teachers calculate grade percentages to evaluate class performance and determine grading curve distributions. Educational institutions publish statistical demographic reports detailing student achievement rates across subjects. Survey data analysis converts frequency counts into percentages for clear public reporting and comparison. Option A drastically overestimates the percentage by using an inverted fraction ratio. Option B miscalculates the decimal division resulting from the student count ratio. Option D underestimates the percentage performance metric by applying an incorrect numerator value.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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