Question 1138774
<br>
b = # of brownies
c = # of chocolate chip cookies<br>
(1) {{{b+c = 175}}}  the total number of items sold was 175
(2) {{{2b+c = 250}}}  the total cost of the items, at $2 each for the brownies and $1 each for the cookies, was $250<br>
Solve the equations by whatever method you choose.  Elimination certainly looks the easiest, since subtracting the first equation from the second immediately give you the value of b:<br>
{{{b = 75}}}<br>
So 75 brownies and 100 chocolate chip cookies were sold.<br>
You can get the answer using virtually the same calculations informally, using logical reasoning instead of formal algebra:<br>
(1) If all 175 items were cookies, the total sales would be $175; but the actual total is $250, which is $75 more than that.
(2) Each brownie costs $1 more than each cookie.
(3) Therefore, to make the additional $75, the number of brownies that was sold has to be $75/$1 = 75.