Anmol was asked to calculate earth Matic mean of 10 positive integers ...
Let the actual average be n. So, the new average is n + 1.8
Actual total = 10n
New total = 10n + 18
Let the number which was miswritten = ab(a is the tenth's digit and b is the units digit) = 10a + b
and reversed number ba = 10b + a
So, 10b + a - (10a + b) = 18
=> 9(b - a) = 18
=> b - a = 2
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Anmol was asked to calculate earth Matic mean of 10 positive integers ...
Calculation Mistake in Arithmetic Mean
Anmol made a mistake by interchanging the two digits a and b in one of the 10 integers while calculating the arithmetic mean.
Given Information
Let's assume the 10 integers are x1, x2, x3, ..., x10. The correct arithmetic mean should have been M.
Anmol's incorrect arithmetic mean calculation (after interchanging digits a and b) is M + 1.8.
Finding the Correct Arithmetic Mean
To find the correct arithmetic mean, we need to first identify the difference between the incorrect and correct arithmetic means.
The difference is 1.8, which means that the sum of the 10 integers was increased by 18 (1.8 * 10).
Finding the Digits a and b
When the digits a and b are interchanged in one of the integers, the difference in the sum of the digits is b - a.
Since the sum of the 10 integers increased by 18, this increase must be due to the difference in the sum of the interchanged digits in one of the integers.
Therefore, b - a = 18.
Conclusion
The difference between the interchanged digits a and b in one of the 10 integers is 18.
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