Question 1134419
.


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;You can solve it &nbsp;<U>MENTALLY</U>, &nbsp;without using equations.



<pre>
After exchange, the total mass of 155 lb consists of 12 + 19 = 31 equal parts.


Each part is then  {{{155/31}}} = 5 lb.


So, after exchange, there are  12*5 = 60 lb in the first box and  19*5 = 95 lb in the second box.


Hence, BEFORE exchange, there were 60+20 = 80 lb in the first box and 95-20 = 75 lb in the second box.    <U>ANSWER</U>
</pre>


Solved.



/\/\/\/\/\/\/\/



I want to remind you that as an educated visitor, you MUST express your thanks to EACH the solution

that I produce in response to your request.



I forced to make this reminder because MANY (if not all) visitors IGNORE THIS RULE.  Unfortunately.


Which I consider as an extreme degree of discourtesy.