Question 1123778
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Let x = Mike's weekly allowance, which is under the question.


Then {{{x/2}}} is what was left after buying the movies tickets.


Plus to it Mike earned 7 dollars.


The condition says 


{{{x/2}}} + 7 = 17.


Then  {{{x/2}}} = 17 - 7 = 10;  hence,  x = 2*10 = 20 dollars.


<U>Answer</U>.  Mike's weekly allowance is 20 dollars.
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