Question
The average marks of 12 students in an exam is (x + 10).
If the average of the first six students is 50 and that of the remaining six is 70, find the value of (x + 30).Solution
According to the question, The average marks of 12 students = (x + 10) = 12 * (x + 10) The total marks of first six students = 6 * 50 = 300 The total marks of last six students = 6 * 70 = 420 300 + 420 = 12 * (x + 10) 720 = 12(x + 10) 60 = x + 10 x = 50 x + 30 = 80
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