Question
The average of five consecutive natural numbers is 12.
What will be the average of the seven numbers if the next two natural numbers are also included?Solution
Let the first natural number be N. According to the question, N + (N + 1) + (N + 2) + (N + 3) + (N + 4) = 12 x 5 5N + 10 = 60 5N = 50 N = 50/5 N = 10 Sum of the seven numbers N+ (N+1) + (N+2) + (N + 3) + (N + 4) + (N+5) + (N + 6) 7N + 21 =7 x 10 + 21=91 Average of the seven numbers = 91/7 = 13 The average of the seven numbers if the next two natural numbers are also included will be 13.
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