Yourself:While finding the average of ‘9’ consecutive numbers starting...
Understanding the Problem:
The student has mistakenly interchanged the digits of the second number while finding the average of 9 consecutive numbers starting from X. This error resulted in an average that is 8 more than the actual average.
Solving the Problem:
Let's assume the 9 consecutive numbers starting from X are X, X+1, X+2, X+3, X+4, X+5, X+6, X+7, and X+8.
The actual average of these numbers would be (X + X+1 + X+2 + X+3 + X+4 + X+5 + X+6 + X+7 + X+8) / 9 = X + 4.
When the student interchanged the digits of the second number, let's say the new number is Y. So, the new series becomes X, Y, X+2, X+3, X+4, X+5, X+6, X+7, and X+8.
The new average is (X + Y + X+2 + X+3 + X+4 + X+5 + X+6 + X+7 + X+8) / 9 = X + 4 + 8 = X + 12.
Finding the Value of X:
Since the new average is 8 more than the actual average, we can equate the two expressions:
X + 12 = X + 4 + 8
X + 12 = X + 12
X = 0
Therefore, the value of X is 0. The 9 consecutive numbers starting from 0 would be 0, 1, 2, 3, 4, 5, 6, 7, and 8.
By following the steps above and understanding the problem thoroughly, we can determine the correct value of X, which is essential in solving this type of mathematical puzzle.
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