Question
The average age of 26 children and their teacher's age
are 22 years. If the teacher's age is excluded, the average reduces by 1. What is the teacher's age?Solution
Sum of the age of total children and teacher = 27 times; 22 = 594 Sum of the age of children after excluding = 26 times; 21 = 546 Teacherrsquo;s age = 594 ndash; 546 = 48 years
Find the mean of the following observations:
45, 54, 42, 56, 46, 48, 52, 50, 57, 43Average 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).
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