Question
A teacher marked a certain average number of papers per
day for the first 30 days. In the next 10 days, she marked 90 papers daily. This increased her overall average by 5 papers per day. What was the average for the first 30 days?Solution
Let, average number of papers marked in first 30 days is x So, (30 × x + 10 × 90)/40 = x + 5 Or, 30x + 900 = 40x + 200 Or, 10x = 700 Or, x = 70
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