SSC GD Constable practice question
Section X of a school has 25 students with an average height of 80 cm above a reference mark, and Section Y has 15 students with an average of 60 cm above the same mark. Find the combined average (above the reference mark) for both sections together.
From a SSC GD Constable Quantitative Aptitude practice set · Quantitative Aptitude
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Correct answer: (B) 72.5 cm
Total number of students = 25 + 15 = 40. Sum of values for the first group = 25 × 80 = 2000. Sum of values for the second group = 15 × 60 = 900. Combined sum = 2000 + 900 = 2900. Combined average = 2900 ÷ 40 = 72.5 cm.
हिंदी में प्रश्न
एक स्कूल के सेक्शन X में 25 विद्यार्थी हैं जिनकी एक निर्धारित रेखा से औसत ऊँचाई 80 सेमी अधिक है, और सेक्शन Y में 15 विद्यार्थी हैं जिनकी औसत ऊँचाई उसी रेखा से 60 सेमी अधिक है। दोनों सेक्शनों को मिलाकर संयुक्त औसत (रेखा से ऊँचाई) ज्ञात कीजिए।
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सही उत्तर: (B) 72.5 सेमी
कुल विद्यार्थियों की संख्या = 25 + 15 = 40. पहले समूह का कुल योग = 25 × 80 = 2000. दूसरे समूह का कुल योग = 15 × 60 = 900. संयुक्त योग = 2000 + 900 = 2900. संयुक्त औसत = 2900 ÷ 40 = 72.5 सेमी.
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