Question
Average of 8 students is 15 years. If two more students
of age 20 and 10 years join. What will be the new average age?Solution
Average = Sum of ages / Total number of students 15 = x / 8 => x = 120 Two more students of 10 and 20 years are added. So, => x = 120 + 20 + 10 => x = 150 ∴ The new average = 150/10 = 15 ∴ The new average is also 15. Thus, it remains same.
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