Question 1138191
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Let x be the number of newspapers John delivers in a day (the value under the question).


Then Bob delivers (x-9) newspapers.


The condition says


    7*(x + (x-9)) = 861.


Simplify and solve for x :


    7x + 7x - 63 = 861

    14x = 861 + 63

    14x = 924

     x  = {{{924/14}}} = 66.


<U>ANSWER</U>.  John delivers 66 newspapers per day.
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