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put this solution on YOUR website! The arithmetic mean of a set of 50 numbers is 38.
Therefore it's the same as if every number were 38.
So the sum of the numbers is 50×38 = 1900
If two numbers 45 and 55 are discarded,
That's subtracting them both from the 1900. 1900 - 45 - 55 = 1800.
1800 is the new sum of the numbers after those 100 were discarded.
So now there are only 48 numbers after those two are discarded.
The new average is
=
= 37.5
the mean of the remaining set of numbers is 37.5.
Edwin