Question
Average marks of 30 students is 76. Two new students
with marks (y + 8) and (y - 12) join, and the average becomes 75. Find (y - 35).Solution
32 × 75 − 30 × 76 = y + 8 + y − 12
2y - 4 = 2400 − 2280 = 120
2y = 124
y = 62
y − 35 = 27
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