Question 1130368
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If a formal algebraic solution is not required, solve it using logical reasoning.<br>
(1) Count the 6 "extra" $5 bills.  That's $30, leaving $105, which now consists of equal numbers of $5 and $10 bills.
(2) One $5 bill and one $10 bill makes $15.
(3) The number of $5 and $10 bills needed to make the remaining $105 is 105/15 = 7.
(4) So, now counting all the bills, there are 7 $10 bills and 7+6 = 13 $5 bills.