Question 1203933
A delivery truck is transporting boxes of two sizes: large and small. The large
boxes weigh 40 pounds each, and the small boxes weigh 25 pounds each. There are
120 boxes in all. If the truck is carrying a total of 3750 pounds in boxes, how
many of each type of box is it carrying?
<pre>
For interesting enrichment in your mathematical thinking about this problem, 
let's look at the "no-algebra" way to do it -- the only way you could have done
it when you were in elementary school!  Some elementary school teachers have
labeled it the "WHAT IF?" method. 
<b><font face="lucida console">
If all 120 boxes had weighed only 25 pounds each, the truck 
would be carrying only (120)(25) = 3000 pounds.  So some of 
the 120 boxes must each weigh 40-25 = 15 pounds heavier to 
cause the cargo to weigh 3750-3000 = 750 pounds heavier. So 
there must be 750/15 = 50 large boxes, and 120-50 = 70 small 
boxes.</b></font>

Or you could go this route instead without using algebra:
<b><font face="lucida console">
If all 120 boxes had weighed 40 pounds each, the truck would 
be carrying (120)(40) = 4800 pounds.  So some of the 120 
boxes must each weigh 40-25 = 15 pounds lighter to cause the 
cargo to weigh 4800-3750 = 1050 pounds lighter.  So there 
must be 1050/15 = 70 small boxes, and 120-70 = 50 large boxes.</b></font>

Edwin</pre>