<PRE><B>Question 1164545</B>
let L = weight of large boxes
let s = weight of small boxes
:
Just write an equation for the given statements
:
A delivery truck is transporting boxes of two sizes: large and small.
 The combined weight of a large box and a small box is 90 pounds.
L + s = 90
we can use this form for substitution 
L = (90-s)
 The truck is transporting 60 large boxes and 65 small boxes.
 If the truck is carrying a total of 5550 pounds in boxes,
60L + 65s = 5550
replace L with (90-s)
60(90-s) + 65s = 5550
5400 - 60s + 65s = 5550
5s = 5550 - 5400
5s = 150
s = 150/5
s = 30 lb is the small box
then
90 - 30 = 60 lb is the large
:
;
Check this
60(60) + 65(30) = 
3600 + 1950 = 5550

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