Question 1143708
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Since the average of a set of 6 numbers is 3.5, the sum of these numbers is 6*3.5 = 21.


Then the sum of 7 numbers is  21 + 4.2 = 25.2  and the average of 7 numbers is  {{{25.2/7}}} = 3.6.    <U>ANSWER</U>
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