Question
The average of five consecutive natural numbers is 14.
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) = 14 x 5 5N + 10 = 70 5N = 60 N = 60/5 N = 12 The sum of the seven numbers N+ (N+1) + (N+2) + (N + 3) + (N + 4) + (N+5) + (N + 6) =7N + 21 =7 x 12 + 21=105 Average of the seven numbers = 105/7 = 15 The average of the seven numbers if the next two natural numbers are also included will be 15.
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