✅
A. If 2^x = 256 / √2, then x = 15/2
256 = 2^8 and √2 = 2^(1/2), so:
256 / √2 = 2^8 / 2^(1/2) = 2^(8 - 1/2) = 2^(15/2)
So, x = 15/2 → Correct
B. 1/3 of 50% of 150 is greater than √576
50% of 150 = 75
1/3 of 75 = 25
√576 = 24
Since 25 > 24 → Correct
❌
C. Rank from top is 5th, total students = 20
So, rank from bottom = 20 - 5 + 1 = 16, not 15 → Incorrect
D. Average of 20 students = 45 kg
Remaining 10 students = average 40 kg
Total weight = (20 × 45) + (10 × 40) = 900 + 400 = 1300
Total students = 30
Average = 1300 / 30 = 43.33 kg, not 42.5 kg → Incorrect
✅
A. यदि 2^x = 256 / √2, तो x = 15/2
256 = 2^8 और √2 = 2^(1/2), अतः:
256 / √2 = 2^8 / 2^(1/2) = 2^(8 - 1/2) = 2^(15/2)
अतः, x = 15/2 → सही
B. 150 के 50% का 1/3, √576 से बड़ा है
150 का 50% = 75
75 का 1/3 = 25
√576 = 24
चूँकि 25 > 24 → सही
❌
C. ऊपर से रैंक 5वीं है, कुल छात्र = 20
अतः, नीचे से रैंक = 20 - 5 + 1 = 16, 15 नहीं → गलत
D. 20 छात्रों का औसत = 45 किग्रा
शेष 10 छात्रों का औसत = 40 किग्रा
कुल भार = (20 × 45) + (10 × 40) = 900 + 400 = 1300
कुल छात्र = 30
औसत = 1300 / 30 = 43.33 किग्रा, 42.5 किग्रा नहीं → गलत
Year-wise PYQs
